release: 3.0.1

Bump the workspace to 3.0.1 and bring the user guide up to date: an RDP
chapter, shell integration and inline images, SSH certificates and CAs,
known_hosts import/export, stored credentials and master password change,
profile sync (replacing the Alchementary Link migration chapter), the
Diagnostics tab and log, and refreshed screenshots throughout. The welcome
screen's protocol line now lists RDP.

.github/copilot-instructions.md

@@ -1,109 +1,86 @@
 # Copilot Instructions — Nexus Terminal
 
+Nexus Terminal is a native desktop client (SSH, Telnet, RAW TCP, Serial, VNC, IRC, GitHub, local shell) written in Rust with an eframe/egui UI. All the code lives in the Cargo workspace under `rust/`.
+
 ## Build & Test
 
 ```bash
-make deps              # go mod download + npm install
-make build             # production build → build/bin/nexus-terminal.app
-make dev               # wails dev with hot reload
-make test              # go test ./... -v -count=1
-make lint              # golangci-lint run ./...
+cd rust
+cargo run --release                                     # the app (binary `nexus-terminal`)
+cargo test --workspace                                  # unit and integration tests
+cargo clippy --workspace --all-targets -- -D warnings   # must be clean
+cargo fmt --all --check                                 # must be clean
 
-# Single package test
-go test ./internal/storage/ -v -count=1 -run TestProfileCRUD
+# Single test
+cargo test -p nexus-core --lib storage::
+cargo test -p nexus-core --test ssh_integration
 ```
 
-The frontend has no separate build step — `npm run build` (called by Wails) copies xterm vendor libs from `node_modules` into `frontend/src/js/lib/` and `frontend/src/css/lib/`. All frontend assets are embedded at compile time via `frontend/embed.go`.
+CI (`.github/workflows/ci.yml`) runs `cargo test --locked`, `cargo fmt --check` and `cargo clippy --all-targets -D warnings` on Linux, macOS and Windows. The toolchain is pinned in `rust/rust-toolchain.toml`. Platform prerequisites and release packaging are in `docs/build-and-release.md`.
 
 ## Architecture
 
-Wails v2 desktop app: Go backend + HTML/CSS/JS frontend rendered in a native webview (WKWebView on macOS).
+The project is engine-first: a UI-free core crate, and the egui app is one client of it.
 
-**Go backend** (`internal/`):
-- `app/` — lifecycle bootstrap: opens SQLite, inits secret stores, wires everything together
-- `api/` — single `Service` struct bound to Wails; every public method is callable from JS as `window.go.api.Service.MethodName()`
-- `sessions/` — manages concurrent protocol sessions; owns SSH/Telnet/RAW/GitHub client lifecycles; handles auto-reconnect, login scripts, broadcast
-- `storage/` — SQLite repository (WAL mode) with embedded sequential migrations in `storage/migrations/`
-- `secrets/` — two-tier credential storage: OS keychain (preferred) → AES-256-GCM encrypted file vault (fallback)
-- `models/` — shared domain types and defaults; protocol configs are JSON-encoded in the DB
-- `sshclient/` — SSH client with agent, TOTP/2FA, and SOCKS5/HTTP proxy support
-- `telnetclient/`, `rawclient/`, `githubclient/` — protocol implementations
-- `sftpclient/` — SFTP file operations (browse, upload, download, rename, delete)
-- `sshconfig/` — OpenSSH `~/.ssh/config` parser and importer
-- `recording/` — asciicast v2 session recording and playback
-- `exportimport/` — encrypted profile bundles (.nexus format)
-- `updater/` — GitHub Releases update checker
-- `knownhosts/` — SSH host key management
-- `validation/` — profile and protocol validation
-- `audit/` — timestamped audit logging
+```
+rust/
+├── core/   nexus-core: storage, secrets, models, protocol clients, session Manager, Service. No egui.
+│   ├── migrations/       numbered SQL migrations, embedded with include_str!
+│   └── tests/            sessions.rs, ssh_integration.rs, fixtures/
+└── app/    nexus: the egui shell (binary `nexus-terminal`)
+```
 
-**Frontend** (`frontend/`):
-- Plain HTML/CSS/JS — no framework, no bundler, no ES modules
-- `index.html` is the app shell; loads CSS then JS in strict order
-- `src/js/` — 18 modules, each IIFE-wrapped, exporting to `window.NexusTerminal`
-- `src/css/` — modular stylesheets; `tokens.css` defines all design tokens
-- Vendor libs (xterm.js, addons) live in `src/js/lib/` and `src/css/lib/` — auto-copied, gitignored
+**Core (`rust/core/src/`):**
+- `service.rs` — `Service`, the app-facing API: profiles, connect/reconnect, credentials, known hosts, preferences, snippets, import/export, SSH keys, SFTP, updates. File dialogs live in the UI; methods here take paths.
+- `sessions.rs` — `Manager`: concurrent sessions, auto-reconnect with backoff, login scripts, broadcast writes, recording hooks, secret resolution (saved / session-only / ask every time), host-key checks. It reports through one `Event` enum (`Data`, `State`, `Closed`, `RawData`, `Irc`, `Github*`, `Forward*`, `Recording*`, `SftpProgress`, `SecretPrompt`, `HostKeyVerify`, `Vnc*`).
+- `clients/` — one module per protocol (`ssh`, `sftp`, `telnet`, `raw`, `serial`, `local`, `irc`, `github`, `vnc`). Read the conventions at the top of `clients/mod.rs` before touching one: `connect()` blocks its (worker) thread and returns once usable; the client then owns its reader thread(s) and reports through `Callbacks` (data, fatal error, close exactly once); `write`/`resize`/`close` are callable from any thread and `close` is idempotent. russh-based clients use the shared tokio runtime from `clients::rt()`; the rest use plain threads.
+- `storage.rs` (SQLite via rusqlite, WAL), `secrets.rs` (keychain + vault), `config.rs` (data directories and Alchementary Link migration), `models.rs`, `validation.rs`, `exportimport.rs`, `recording.rs` (asciicast v2), `sshconfig.rs`, `updater.rs`, `ircformat.rs`, `terminalenv.rs`, `keyfiles.rs`.
 
-**Go ↔ JS communication:**
-- **Synchronous:** Frontend calls `window.go.api.Service.*()` (returns Promise)
-- **Asynchronous:** Backend pushes events via `wailsRuntime.EventsEmit()`; frontend listens with `window.runtime.EventsOn()`
-- **Bidirectional events** for secret prompts and host key verification: backend emits a request event with a `requestID`, frontend shows a modal, then emits a response event with the same ID. The Go side blocks on a channel keyed by that ID.
+**App (`rust/app/src/`):**
+- `main.rs` parses flags, opens the `Service` and starts eframe. `app.rs` owns `App`: it installs an event sink that forwards `Event`s over a channel and calls `request_repaint`, drains them each frame (`on_event`), handles `Request`s, the keyboard shortcuts (`shortcuts()`), and lays out the frame.
+- `state.rs` — `Shared` (service handle, cached profiles and preferences, tabs, panes, toasts) and the `Request` queue features use to ask the main window to act.
+- `views.rs` — `View::{Terminal, Raw, Irc, Github, Vnc}`, one per pane.
+- `terminal.rs` (`TermView`: alacritty_terminal drawn with egui's painter), `tabs.rs` (tab strip, workspace, find bar, overlays), `splits.rs` (split tree), `sidebar.rs`, `chrome.rs` (title bar, status bar, command palette `Cmd` enum, prompts, dialogs, toasts).
+- Feature windows: `profile_editor.rs`, `quick_connect.rs`, `settings.rs` (including the Help topics), `ssh_keys.rs`, `transfer.rs` (import/export), `sftp.rs`, `forwards.rs`, `snippets.rs`, `triggers.rs`, `recordings.rs`.
+- Protocol views: `raw_view.rs`, `irc_view.rs`, `github_view.rs`, `vnc_view.rs`.
 
-Key events: `session:data`, `session:state`, `session:closed`, `session:raw:data`, `session:github:repos`, `session:secret:prompt`/`session:secret:response`, `session:hostkey:verify`/`session:hostkey:response`.
-
-## WKWebView Constraints (Critical)
-
-The macOS webview silently blocks or breaks several standard web APIs. These constraints affect every frontend change:
-
-1. **No `window.confirm()`, `window.prompt()`, `window.alert()`** — they either return false/null silently or do nothing. All user prompts must use the custom modal system (DOM-based backdrop + modal with `is-visible` class toggling).
-
-2. **No ES modules** — `<script type="module">` fails silently. All JS files use plain `<script>` tags and IIFE wrappers: `(function() { ... })();`
-
-3. **Click swallowing on text-selectable elements** — WKWebView initiates a text selection gesture on `mousedown` for `<div>` elements, which swallows the first `click` event (appears to require double-click). Fix: add `mousedown` handler with `e.preventDefault()` on any clickable non-input element (section headers, list items, etc.).
-
-4. **Modal visibility pattern** — both `.modal-backdrop` AND `.modal` elements start with `opacity: 0; visibility: hidden` in CSS. You must add the `is-visible` class to **both** elements, not just the backdrop.
-
-5. **Wails runtime injection** — `window.go` and `window.runtime` are injected by Wails before scripts execute. Do NOT add explicit script tags for Wails scripts. The frontend polls for their availability at startup (max 5s).
+**Flow:** UI → `Service` / `Manager` method (plain Rust call) → protocol client on a worker thread → `Callbacks` → `Manager` emits `Event` → app channel → `App::on_event` on the next frame. Credential and host-key questions are `Event::SecretPrompt` / `Event::HostKeyVerify` carrying an `mpsc::Sender` reply; the connecting thread blocks on the receiver, and dropping the sender (closing the prompt or the session) cancels it.
 
 ## Conventions
 
-**Language:** All code comments in British English (colour, initialise, behaviour, etc.).
+- **British English** in comments, docs and UI strings (colour, initialise, behaviour, favourite).
+- **Never block the UI thread.** Anything that touches the network, the keychain, `ssh-keygen` or slow disk work runs on a worker thread: `Shared::spawn` (errors become toasts), `settings::Job` (poll a result each frame), or a module's own inbox. Call `ctx.request_repaint()` when the work finishes. Quick SQLite calls through `Service` are fine inline.
+- **Colours come from `Tokens`** (`theme.rs`, `Tokens::get(ctx)`): `text`, `text_dim`, `text_faint`, `accent`, `success`, `warning`, `danger`, `field`, `card`, `dock`, … Don't hard-code colours; all three app themes (Pro, Midnight, Light) must work. Protocol colours and badges come from `views::protocol_color` / `protocol_badge`; terminal palettes from `terminal_themes.rs`.
+- **Icons are Phosphor** (`egui_phosphor::regular as icon`), usually as `format!("{}  Label", icon::X)`. Reuse the helpers in `widgets.rs` (`primary`, `button`, `icon_button`, `hint`, `empty`, `chip`, `section`, `kv`) and `chrome::modal` for modal dialogs.
+- **Shortcut labels** go through `state::keys("Mod+Shift+K")`, which renders ⌘ on macOS and Ctrl elsewhere. A new shortcut needs an entry in `App::shortcuts()`, the command palette (`chrome::commands`), the menu, the Help "Keyboard Shortcuts" topic and the README table.
+- **Formatting:** `rustfmt.toml` sets `max_width = 160` with `use_small_heuristics = "Max"`, so long single-line expressions are normal. Run `cargo fmt --all` rather than wrapping by hand.
+- Errors are `nexus_core::Result<T>` (`Box<dyn Error + Send + Sync>`); use `?` and `format!` messages that read well in a toast.
+- Protocol configs are `Option<…Config>` fields on `Profile` (`ssh`, `telnet`, `raw`, `github`, `vnc`, `irc`, `serial`), stored as JSON columns; `Profile::new(protocol)` fills the defaults, and the structs use `#[serde(default)]` so older rows still load.
+- A `ponytail:` comment marks a deliberate simplification and names its limit; keep them accurate when you change that code.
 
-**Go patterns:**
-- String-typed enums: `type Protocol string` with `const ProtocolSSH Protocol = "ssh"` etc.
-- Protocol configs are pointer fields on `Profile` (`SSH *SSHConfig`, `Telnet *TelnetConfig`, etc.) — nil when not applicable
-- `NewProfile(protocol)` factory in `defaults.go` populates sensible defaults per protocol
-- Storage uses `nullableJSON()` helper to write nil for unused config columns
-- Tests use `t.TempDir()` for isolation, `t.Fatalf()` for setup failures
+**Adding a protocol** touches: `models.rs` (`Protocol`, config struct, defaults, labels), `validation.rs`, a new migration (CHECK constraint and config column) plus the column lists in `storage.rs`, a client in `clients/`, the `Manager` connect/close/write paths in `sessions.rs`, the profile editor section, Quick Connect if relevant, a view (or `TermView` for terminal protocols), `views::protocol_badge`/`protocol_color`, the palette, and a Help topic.
 
-**Frontend patterns:**
-- Every JS file is IIFE-wrapped and exports to `window.NexusTerminal` namespace
-- Script load order matters (defined in `index.html`) — utils → state → notifications → sidebar → tabs → themes → terminal → profiles → raw → github → settings → commands → secrets → recordings → sftp → splitpane → snippets → app
-- DOM helpers: `createElement(tag, className, attrs)` from utils.js (supports `textContent`, `innerHTML`, `dataset`, `on*` event handlers)
-- Profile editor uses `_renderSection(title, fields)` pattern with `_field(type, name, label, value, opts)` helper for form generation
-- Login script editor uses `_renderLoginScriptSection(prefix, steps)` for expect-style step lists
-- TOTP section uses `_renderTOTPSection(profile)` with encrypted vault storage
-- `protocolColour()` returns CSS class names like `proto-ssh`; tab badges use `badge-ssh` class naming (different pattern)
+## Data compatibility (hard rules)
 
-**CSS patterns:**
-- Design tokens in `tokens.css`: `--bg-base`, `--bg-surface`, `--bg-elevated`, `--text-primary`, `--accent`, `--protocol-ssh`, etc.
-- Dark charcoal palette — not Material Design literally, but Material-inspired layering
-- Protocol colours: SSH=teal `#4ecdc4`, Telnet=amber `#ffa726`, RAW=purple `#ab47bc`, GitHub=indigo `#7c8aff`
+Existing users upgrade in place, and their data came from the Go app first. Nexus Terminal must keep reading it.
 
-**Adding a new protocol:**
-1. Add `Protocol` constant + config struct in `models/models.go`
-2. Add defaults in `models/defaults.go` `NewProfile()` switch
-3. Create client package in `internal/<proto>client/`
-4. Add `connect<Proto>()` in `sessions/manager.go` + case in `Connect()` switch
-5. Add API methods in `api/api.go` if needed
-6. Add DB migration in `storage/migrations/` (update CHECK constraint, add config column)
-7. Update `storage/store.go`: all SELECT/INSERT/UPDATE queries + both scan functions
-8. Frontend: add DEFAULTS in `profiles.js`, render sections, collect form values, protocol tab
-9. Frontend: add viewer in new JS file (IIFE-wrapped), include in `index.html`, wire in `app.js`
-10. Add CSS: protocol colour token, sidebar indicator, tab badge, viewer styles
+- **Never change the database, vault, export or recording formats incompatibly.** The vault (`vault/vault.json`: Argon2id t=3, m=128 MiB, 4 lanes; AES-256-GCM per secret), the export envelope (`[version][32-byte salt][12-byte nonce][ciphertext]`, `.nexus`; `.link` must still import) and asciicast v2 recordings are fixed.
+- **Fixtures** generated by the old Go app live in `rust/core/tests/fixtures/` (`link.db`, `vault/`, `profiles.link`, `recordings/`). Tests in `storage.rs`, `secrets.rs`, `exportimport.rs` and `recording.rs` read them. Don't regenerate or edit them to make a test pass.
+- **Schema changes are new SQL files** in `rust/core/migrations/` (`008_….sql`, …), added to `MIGRATIONS` in `storage.rs`. Each ends with `INSERT INTO schema_version (version, applied_at) VALUES (N, datetime('now'));`. Never edit an applied migration. SQLite has no `ALTER COLUMN`; use the recreate-table pattern.
+- **Keychain** entries are stored under the service `NexusTerminal`; reads fall back to `AlchementaryLink` and copy forward. Don't change key names (`profile:<id>:<kind>`).
+- **Data directory** names (`NexusTerminal`, `nexus.db`, `vault/`, `recordings/`) and the first-run migration from `AlchementaryLink/` in `config.rs` are user-facing; keep them stable.
 
-**Database migrations:**
-- Numbered SQL files: `001_initial.sql`, `002_github_protocol.sql`, etc.
-- Each must `INSERT INTO schema_version (version, applied_at) VALUES (N, datetime('now'))` at the end
-- SQLite has no `ALTER COLUMN` — use the recreate-table pattern (CREATE new → INSERT INTO new SELECT FROM old → DROP old → ALTER TABLE RENAME)
-- Every query in `store.go` that touches the profiles table must be updated when columns change (there are ~8 SELECT column lists + 2 scan functions)
+## Testing tips
+
+- **Never point a test or manual run at your real data.** Use `--data-dir DIR` (a temporary directory) for manual runs; tests create their own directory under `std::env::temp_dir()`, as the existing ones do.
+- **App flags** (`rust/app/src/main.rs`):
+  - `--data-dir DIR` — use another data directory.
+  - `--screenshot out.png` — render, save a PNG and exit (works under `xvfb-run`); combine with `--size WxH` and `--theme pro|midnight|light`.
+  - `--open WINDOW` — open a window at startup: `editor[:protocol|id]`, `quick`, `settings[:terminal|security|knownhosts|help|about]`, `keys`, `snippets`, `triggers`, `recordings`, `palette`, `export`, `import`.
+  - `--connect NAME` — connect a saved profile by display name or id.
+  - `--run-local CMD` — open a local terminal and type `CMD` into it once connected.
+
+  For example: `cargo run -- --data-dir /tmp/nx --open settings:help --screenshot /tmp/help.png`.
+- **SSH integration tests** (`core/tests/ssh_integration.rs`) start a throwaway `sshd` as the current user on a random port and skip themselves when OpenSSH isn't installed. They **must never open an interactive login shell** — the user's shell profile can auto-attach tmux/byobu to a real session. Set the profile's startup command to `/bin/sh -i`, as the existing `profile()` helper does.
+- `core/tests/sessions.rs` drives the `Manager` end to end against local TCP listeners; follow its `manager()` and `wait()` helpers for event-driven tests.
+- UI logic that can be tested without a window (parsers, fuzzy matching, split trees, snippet variables, trigger matching) has `#[cfg(test)]` unit tests next to it; add one with any non-trivial change.

.github/workflows/ci.yml

@@ -0,0 +1,44 @@
+name: CI
+
+on:
+    push:
+        branches: ["**"]
+    pull_request:
+
+permissions:
+    contents: read
+
+jobs:
+    test:
+        name: Test (${{ matrix.os }})
+        runs-on: ${{ matrix.os }}
+        strategy:
+            fail-fast: false
+            matrix:
+                os: [ubuntu-22.04, macos-14, windows-latest]
+        defaults:
+            run:
+                shell: bash
+                working-directory: rust
+        steps:
+            - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4.4.0
+            - name: Linux dependencies (GUI libs, and sshd for the SSH integration tests)
+              if: runner.os == 'Linux'
+              run: |
+                  sudo apt-get update
+                  sudo apt-get install -y libxkbcommon-dev libgl1-mesa-dev libx11-dev libxcursor-dev libxrandr-dev libxi-dev libwayland-dev libgtk-3-dev libasound2-dev openssh-server
+            - run: cargo test --locked --workspace
+            - run: cargo fmt --all --check
+            - run: cargo clippy --locked --workspace --all-targets -- -D warnings
+
+    audit:
+        name: Dependency audit
+        runs-on: ubuntu-22.04
+        defaults:
+            run:
+                working-directory: rust
+        steps:
+            - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4.4.0
+            - run: cargo install cargo-audit --locked
+            # Ignored advisories and their reasons live in rust/.cargo/audit.toml.
+            - run: cargo audit

.github/workflows/fuzz.yml

@@ -0,0 +1,33 @@
+name: Fuzz
+
+on:
+    schedule:
+        - cron: "17 3 * * *"
+    workflow_dispatch:
+
+permissions:
+    contents: read
+
+jobs:
+    fuzz:
+        name: Fuzz (${{ matrix.target }})
+        runs-on: ubuntu-22.04
+        strategy:
+            fail-fast: false
+            matrix:
+                target: [telnet, irc, vnc, sshconfig, updater]
+        defaults:
+            run:
+                working-directory: rust/fuzz
+        steps:
+            - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4.4.0
+            - run: sudo apt-get update && sudo apt-get install -y libasound2-dev
+            - run: rustup toolchain install nightly --profile minimal
+            - run: cargo +nightly install cargo-fuzz --locked
+            - run: cargo +nightly fuzz run ${{ matrix.target }} -- -max_total_time=120 -rss_limit_mb=2048
+            - name: Upload crashing inputs
+              if: failure()
+              uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+              with:
+                  name: fuzz-${{ matrix.target }}
+                  path: rust/fuzz/artifacts

.github/workflows/release-builds.yml

@@ -17,121 +17,50 @@ jobs:
             fail-fast: false
             matrix:
                 include:
-                    - platform: darwin/amd64
-                      runner: macos-13
-                      os: darwin
-                      arch: amd64
-                      archive_type: zip
-                    - platform: darwin/arm64
-                      runner: macos-14
-                      os: darwin
-                      arch: arm64
-                      archive_type: zip
-                    - platform: linux/amd64
-                      runner: ubuntu-latest
-                      os: linux
-                      arch: amd64
-                      archive_type: tar
-                    - platform: linux/arm64
-                      runner: ubuntu-24.04-arm64
-                      os: linux
-                      arch: arm64
-                      archive_type: tar
-                    - platform: windows/amd64
-                      runner: windows-latest
-                      os: windows
-                      arch: amd64
-                      archive_type: zip
-                    - platform: windows/arm64
-                      runner: ubuntu-latest
-                      os: windows
-                      arch: arm64
-                      archive_type: zip
-                      cross: true
-
+                    - { platform: darwin/amd64, runner: macos-13 }
+                    - { platform: darwin/arm64, runner: macos-14 }
+                    - { platform: linux/amd64, runner: ubuntu-22.04 }
+                    - { platform: linux/arm64, runner: ubuntu-22.04-arm }
+                    - { platform: windows/amd64, runner: windows-latest }
+                    - { platform: windows/arm64, runner: windows-11-arm }
+        defaults:
+            run:
+                shell: bash
+                working-directory: rust
         steps:
-            - name: Checkout
-              uses: actions/checkout@v4
-
-            - name: Set up Go
-              uses: actions/setup-go@v5
+            - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4.4.0
               with:
-                  go-version-file: go.mod
+                  fetch-depth: 0
 
-            - name: Set up Node
-              uses: actions/setup-node@v4
-              with:
-                  node-version: "20"
+            - name: Rust toolchain (pinned by rust-toolchain.toml)
+              run: rustup show active-toolchain || rustup toolchain install
 
-            - name: Install Wails
-              run: go install github.com/wailsapp/wails/v2/cmd/wails@latest
-
-            - name: Install frontend dependencies
-              run: npm install
-              working-directory: frontend
-
-            - name: Install Linux build dependencies
-              if: matrix.os == 'linux'
+            - name: Linux build dependencies
+              if: runner.os == 'Linux'
               run: |
                   sudo apt-get update
-                  sudo apt-get install -y libgtk-3-dev libwebkit2gtk-4.0-dev
+                  sudo apt-get install -y libxkbcommon-dev libgl1-mesa-dev libx11-dev libxcursor-dev libxrandr-dev libxi-dev libwayland-dev libgtk-3-dev libasound2-dev zip
 
-            - name: Install Windows cross-compiler
-              if: matrix.os == 'windows' && matrix.cross
-              run: |
-                  sudo apt-get update
-                  sudo apt-get install -y gcc-mingw-w64-x86-64 gcc-mingw-w64-aarch64 zip
+            - name: Test
+              run: cargo test --locked --workspace
 
-            - name: Build (non-Windows runners)
-              if: matrix.runner != 'windows-latest'
+            - name: Build and package
               env:
-                  CGO_ENABLED: "1"
-              run: |
-                  if [ "${{ matrix.os }}" = "windows" ] && [ "${{ matrix.cross }}" = "true" ]; then
-                    export CC=aarch64-w64-mingw32-gcc
-                  fi
-                  wails build -platform "${{ matrix.platform }}" -ldflags "-s -w"
+                  NEXUS_RELEASE_TARGETS: ${{ matrix.platform }}
+                  NEXUS_RELEASE_ROOT: ${{ github.workspace }}/build/releases
+              run: ./release.sh
 
-            - name: Build (Windows runner)
-              if: matrix.runner == 'windows-latest'
-              shell: pwsh
-              env:
-                  CGO_ENABLED: "1"
-              run: |
-                  wails build -platform "${{ matrix.platform }}" -ldflags "-s -w"
-
-            - name: Package (zip)
-              if: matrix.archive_type == 'zip' && matrix.runner != 'windows-latest'
-              run: |
-                  archive="nexus-terminal-${{ matrix.platform }}.zip"
-                  cd build/bin
-                  zip -r "../../${archive}" .
-
-            - name: Package (tar)
-              if: matrix.archive_type == 'tar'
-              run: |
-                  archive="nexus-terminal-${{ matrix.platform }}.tar.gz"
-                  tar -czf "${archive}" -C build/bin .
-
-            - name: Package (Windows zip)
-              if: matrix.archive_type == 'zip' && matrix.runner == 'windows-latest'
-              shell: pwsh
-              run: |
-                  $archive = "nexus-terminal-${{ matrix.platform }}.zip"
-                  Compress-Archive -Path "build/bin/*" -DestinationPath $archive
-
-            - name: Upload artifact
-              uses: actions/upload-artifact@v4
+            - name: Upload artefacts
+              uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
               with:
-                  name: nexus-terminal-${{ matrix.platform }}
+                  name: nexus-terminal-${{ matrix.runner }}
                   path: |
-                      nexus-terminal-${{ matrix.platform }}.zip
-                      nexus-terminal-${{ matrix.platform }}.tar.gz
+                      build/releases/*/NexusTerminal-*.zip
+                      build/releases/manifest-*.json
+                      build/releases/version-*.txt
 
             - name: Attach to GitHub Release
               if: startsWith(github.ref, 'refs/tags/')
-              uses: softprops/action-gh-release@v2
+              uses: softprops/action-gh-release@3bb12739c298aeb8a4eeaf626c5b8d85266b0e65 # v2.6.2
               with:
-                  files: |
-                      nexus-terminal-${{ matrix.platform }}.zip
-                      nexus-terminal-${{ matrix.platform }}.tar.gz
+                  files: build/releases/*/NexusTerminal-*.zip

.gitignore

@@ -3,31 +3,8 @@
 # ==========================================================================
 
 # ── Build output ──────────────────────────────────────────────────────────
-build/bin/
-dist/
-
-# ── Build platform resources (tracked — icons, plists, manifests) ─────────
-# build/darwin/, build/windows/, build/linux/ are tracked for icons & metadata
-
-# ── Go ────────────────────────────────────────────────────────────────────
-vendor/
-*.exe
-*.exe~
-*.dll
-*.so
-*.dylib
-*.test
-*.out
-__debug_bin*
-coverage.out
-coverage.html
-
-# ── Frontend ──────────────────────────────────────────────────────────────
-frontend/node_modules/
-frontend/src/js/lib/
-
-# ── Wails auto-generated bindings (recreated on every build) ──────────────
-frontend/wailsjs/
+rust/target/
+build/releases/
 
 # ── IDE / editor ──────────────────────────────────────────────────────────
 .idea/
@@ -35,20 +12,12 @@ frontend/wailsjs/
 *.swp
 *.swo
 *~
-*.sublime-project
-*.sublime-workspace
-.project
-.classpath
-.settings/
 
 # ── OS metadata ───────────────────────────────────────────────────────────
 .DS_Store
-.DS_Store?
 ._*
 Thumbs.db
-ehthumbs.db
 Desktop.ini
-$RECYCLE.BIN/
 
 # ── Application data (never commit user data or secrets) ──────────────────
 *.db
@@ -57,9 +26,12 @@ $RECYCLE.BIN/
 vault.json
 *.pem
 *.key
-!build/appicon.png
 
+# Compatibility fixtures generated from the last Go build are deliberate test data.
+!rust/core/tests/fixtures/**
 
-# Builds
-build/releases/v*
-build/releases/manifest*
+# Agent worktrees
+.claude/worktrees/
+
+# User guide LaTeX output
+docs/guide/build/

20260602-1221-securityAudit.md

@@ -0,0 +1,787 @@
+# Security Audit Report
+
+## 1. Executive Summary
+
+This audit reviewed Nexus Terminal, a Wails desktop SSH/Telnet/RAW/VNC/SFTP client with a Go backend and JavaScript frontend. Fix mode was requested, so confirmed issues were patched, regression-tested, and prepared for commit.
+
+The highest-risk issues were SSH trust failures: regular SSH sessions were not wired to the existing known-host verification flow, jump-host SSH connections ignored host keys, and VNC SSH tunnels also ignored host keys. These could allow machine-in-the-middle attacks against SSH credentials and terminal/VNC traffic. This run wired all SSH paths to known-host verification and prompt handling.
+
+Other fixed issues include a local noVNC WebSocket proxy access-control weakness, SSH key-name path traversal in public-key reads, unsafe update-result DOM rendering, inline secret leakage in non-secret profile exports, and current vulnerable dependency versions in `golang.org/x/crypto` and `esbuild`.
+
+Residual risk remains in user-selected insecure modes such as direct unencrypted VNC, user-configured `HostKeyInsecure`, and large local file transfer workflows that still process complete files in memory.
+
+## 2. Scope Reviewed
+
+Reviewed:
+
+- Go backend packages under `internal/`: API bindings, sessions, SSH, VNC, SFTP, storage, secrets, updater, raw/telnet clients, recording, validation, known hosts, config, app startup.
+- Frontend JavaScript under `frontend/src/js`: settings/update UI, host-key event handling, terminal and SFTP/VNC/GitHub surfaces, common DOM helpers.
+- Dependency manifests and lockfiles: `go.mod`, `go.sum`, `frontend/package.json`, `frontend/package-lock.json`.
+- Build and release scripts: `Makefile`, `build.sh`, `release.sh`, Wails config.
+- Tests under `internal/**/*_test.go`.
+
+Not in scope:
+
+- Live network penetration testing of remote hosts.
+- Reverse engineering packaged binaries.
+- Manual verification of Wails runtime origin values in a built app.
+
+## 3. Methodology
+
+- Static source review of trust boundaries, file operations, SSH/VNC flows, Wails API bindings, frontend DOM sinks, update checks, storage, crypto, and secret handling.
+- Dependency review with `govulncheck` and `npm audit`.
+- Configuration review of Wails, build scripts, update manifests, and release paths.
+- Threat modelling of desktop renderer compromise, local web-origin attacks, remote SSH/VNC attackers, and malicious update metadata.
+- Denial-of-service review of network timeouts, WebSocket proxy behavior, transfer paths, and file ingestion.
+- Regression tests added for fixed Go issues.
+
+## 4. Risk Rating Method
+
+Severity considered exploitability, attacker position, affected security property, and impact:
+
+- Critical: practical remote compromise or credential disclosure without meaningful preconditions.
+- High: credential/session compromise or machine-in-the-middle exposure on primary connection paths.
+- Medium: meaningful local, renderer, or network-assisted exploit with constraints.
+- Low: hardening issue, local DoS, or user-assisted exposure.
+- Informational: checked area or non-security note.
+
+Confidence reflects direct code evidence and verification coverage.
+
+## 5. Findings Summary Table
+
+| ID | Severity | Confidence | Title | Component | Status |
+|---|---:|---:|---|---|---|
+| SEC-001 | High | High | SSH sessions and jump hosts bypassed known-host verification | SSH sessions | Fixed |
+| SEC-002 | High | High | VNC SSH tunnels accepted any SSH host key | VNC over SSH | Fixed |
+| SEC-003 | Medium | High | Local noVNC WebSocket proxy used a guessable root endpoint | VNC WebSocket proxy | Fixed |
+| SEC-004 | Medium | High | SSH public-key read accepted traversal key names | SSH key API | Fixed |
+| SEC-005 | Medium | High | Update metadata rendered through dynamic HTML and inline handler | Settings/update UI | Fixed |
+| SEC-006 | Medium | High | Non-secret profile export leaked inline SSH secrets | Profile export | Fixed |
+| SEC-007 | High | High | `golang.org/x/crypto` vulnerable in reachable SSH code | Go dependencies | Fixed |
+| SEC-008 | Medium | High | `esbuild` dev dependency matched current npm advisory | Frontend dependency | Fixed |
+| SEC-009 | Low | Medium | Large local file upload paths remain memory-heavy | File transfer UX | Open |
+| SEC-010 | Low | Medium | Direct VNC remains unencrypted by protocol choice | VNC direct mode | Open |
+
+## 6. Detailed Findings
+
+### Finding ID: SEC-001
+
+#### Title
+
+SSH sessions and jump hosts bypassed known-host verification
+
+#### Severity
+
+High
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/sessions/manager.go`, SSH connection setup, now fixed at lines 657 and 1450-1502.
+- `internal/sshclient/sshclient.go`, jump-host config, now fixed at lines 599 and 646-652.
+- `frontend/src/js/app.js`, host-key response correlation, now fixed at lines 334-342.
+
+#### Description
+
+The project already contained known-host storage, a host-key verifier, and frontend prompt UI, but the main SSH session manager previously called the SSH client's default `Connect` path. That default path used `ssh.InsecureIgnoreHostKey()`. Jump hosts also built their own `ssh.ClientConfig` with `ssh.InsecureIgnoreHostKey()`.
+
+#### Evidence
+
+The fix now calls `ConnectWithHostKeyCallback(...)` for regular SSH sessions and propagates the final host-key callback into jump-host configs. A request ID is included in host-key prompt responses to prevent cross-session prompt confusion.
+
+#### Attack Scenario
+
+An attacker on the network path presents a fake SSH server or jump host. Without host-key verification, Nexus Terminal would accept the attacker's key, allowing credential capture, terminal tampering, or traffic interception.
+
+#### Impact
+
+Possible SSH credential theft, terminal command tampering, and loss of server authenticity.
+
+#### Recommendation
+
+Always use the known-host verifier for every SSH hop. Unknown host keys should follow the configured profile policy: strict, ask, accept-new, or explicit insecure.
+
+#### Safer Example
+
+Implemented: `Manager.hostKeyCallback` builds `sshclient.NewHostKeyVerifier(...)`, emits a prompt when needed, and `connectSSH` calls `ConnectWithHostKeyCallback(...)`.
+
+#### Suggested Tests
+
+Added regression coverage:
+
+- `TestHostKeyCallbackAcceptNewStoresHost`
+- `TestHostKeyCallbackStrictRejectsUnknownHost`
+- `TestJumpHostClientConfigUsesFinalHostKeyCallback`
+
+#### References
+
+- CWE-295: Improper Certificate Validation, analogous host-key trust failure.
+- OWASP ASVS 9.1.2: server certificate validation principles.
+
+#### Assumptions / Limitations
+
+Profiles may still explicitly choose `HostKeyInsecure`; that is a user-selected insecure mode and remains visible as residual risk.
+
+### Finding ID: SEC-002
+
+#### Title
+
+VNC SSH tunnels accepted any SSH host key
+
+#### Severity
+
+High
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/vncclient/vncclient.go`, VNC SSH config, now fixed at lines 49 and 89-95.
+- `internal/sessions/manager.go`, VNC SSH callback wiring, now fixed at line 1016.
+
+#### Description
+
+VNC SSH tunnels established SSH connections with `ssh.InsecureIgnoreHostKey()`, allowing a network attacker to impersonate the SSH tunnel endpoint.
+
+#### Evidence
+
+The VNC client now requires `SSHHostKeyCallback` for tunneled SSH. The session manager supplies the same known-host/prompt path used by SSH sessions.
+
+#### Attack Scenario
+
+An attacker controlling DNS, Wi-Fi, or a gateway presents a fake SSH tunnel host for VNC traffic. The prior client accepted the key and tunneled VNC traffic through the attacker.
+
+#### Impact
+
+Possible VNC credential exposure, remote desktop traffic interception, and remote interaction tampering.
+
+#### Recommendation
+
+Require known-host verification for VNC SSH tunnels and reject tunnel setup if no callback is configured.
+
+#### Safer Example
+
+Implemented: `vncclient.Connect` returns an error if `cfg.SSHHostKeyCallback` is nil, and uses the provided callback in `ssh.ClientConfig`.
+
+#### Suggested Tests
+
+Covered indirectly by session host-key callback tests and VNC package tests.
+
+#### References
+
+- CWE-295.
+- OWASP ASVS 9.1.2.
+
+#### Assumptions / Limitations
+
+VNC tunnel host-key policy defaults to ask mode because VNC profiles do not currently expose a separate host-key policy field.
+
+### Finding ID: SEC-003
+
+#### Title
+
+Local noVNC WebSocket proxy used a guessable root endpoint
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/vncclient/vncclient.go`, WebSocket proxy setup, now fixed at lines 171-183 and 255-260.
+
+#### Description
+
+The local VNC WebSocket proxy listened on `127.0.0.1` with a random port, but accepted upgrades on `/` and allowed any Origin. A malicious local web page could scan localhost ports and attempt to connect to an active proxy.
+
+#### Evidence
+
+The proxy now generates a 128-bit random token and exposes only `ws://127.0.0.1:<port>/<token>` to the Wails frontend.
+
+#### Attack Scenario
+
+A user visits a malicious web page while a VNC session is active. The page scans localhost WebSocket ports and connects to the proxy endpoint, potentially reading or injecting VNC traffic.
+
+#### Impact
+
+Possible local cross-origin access to VNC session traffic if the port is discovered.
+
+#### Recommendation
+
+Require an unguessable per-session URL token and continue binding only to loopback.
+
+#### Safer Example
+
+Implemented: `newProxyToken()` uses `crypto/rand` and the proxy route is registered only at the token path.
+
+#### Suggested Tests
+
+Added `TestNewProxyTokenIsRandomHex`.
+
+#### References
+
+- CWE-346: Origin Validation Error.
+- OWASP ASVS 14.4.3: cross-origin resource restrictions.
+
+#### Assumptions / Limitations
+
+`CheckOrigin` still returns true because Wails/noVNC origin behavior needs built-app verification. The unguessable path materially reduces exposure.
+
+### Finding ID: SEC-004
+
+#### Title
+
+SSH public-key read accepted traversal key names
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/api/api.go`, SSH key API, now fixed at lines 1653-1708.
+
+#### Description
+
+`GetSSHPublicKey(name)` previously built `~/.ssh/<name>.pub` directly from a renderer-provided name. Unlike key generation, it did not restrict names to simple key basenames. Names such as `../somefile` could read `~/.ssh/../somefile.pub`.
+
+#### Evidence
+
+The fix centralizes key name validation through `sshKeyPairPaths(...)`, allowing only alphanumeric characters, hyphens, and underscores.
+
+#### Attack Scenario
+
+If renderer-side JavaScript is compromised or a malicious plugin/flow can invoke the Wails API, it can request public-key contents outside the intended `.ssh` key namespace if the target path ends in `.pub`.
+
+#### Impact
+
+Local file disclosure for matching `.pub` paths under paths reachable through traversal.
+
+#### Recommendation
+
+Treat key names as basenames, not paths. Apply the same validation to generate, read, and delete operations.
+
+#### Safer Example
+
+Implemented: `GetSSHPublicKey`, `GenerateSSHKey`, and `DeleteSSHKey` now all use `sshKeyPairPaths`.
+
+#### Suggested Tests
+
+Added:
+
+- `TestSSHKeyPairPathsAcceptsSafeName`
+- `TestSSHKeyPairPathsRejectsTraversal`
+- `TestSSHKeyPairPathsRejectsNestedPath`
+
+#### References
+
+- CWE-22: Path Traversal.
+
+#### Assumptions / Limitations
+
+The API still intentionally lists and reads legitimate SSH public keys in `~/.ssh`.
+
+### Finding ID: SEC-005
+
+#### Title
+
+Update metadata rendered through dynamic HTML and inline handler
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `frontend/src/js/settings.js`, update-check UI, now fixed at lines 940-958.
+
+#### Description
+
+Update metadata from GitHub or a configured update manifest was inserted into `innerHTML`, including an inline `onclick` that interpolated `info.releaseURL`. A malicious or compromised update metadata source could inject script into the Wails renderer.
+
+#### Evidence
+
+The fix constructs DOM nodes, sets text via `textContent`, and attaches a click listener with `addEventListener`.
+
+#### Attack Scenario
+
+An attacker controlling a self-hosted update manifest returns a release URL containing a quote and JavaScript payload. The prior inline handler interpolation could execute renderer JavaScript.
+
+#### Impact
+
+Renderer code execution. In a Wails app, renderer execution can call exposed backend APIs, increasing impact.
+
+#### Recommendation
+
+Never render remote metadata through string-built HTML. Use `textContent` and event listeners.
+
+#### Safer Example
+
+Implemented in `settings.js` with `createElement`, `document.createTextNode`, and `addEventListener`.
+
+#### Suggested Tests
+
+No frontend unit harness exists. Verified with `npm run build`.
+
+#### References
+
+- CWE-79: Cross-Site Scripting.
+- OWASP ASVS 5.3: output encoding.
+
+#### Assumptions / Limitations
+
+Other static modal templates still use `innerHTML`; reviewed high-risk dynamic remote metadata paths first.
+
+### Finding ID: SEC-006
+
+#### Title
+
+Non-secret profile export leaked inline SSH secrets
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/api/api.go`, Wails export wrapper, now fixed at lines 683-684.
+- `internal/storage/store.go`, storage export, now fixed at lines 356-358 and 726-738.
+
+#### Description
+
+The plain profile export path accepted `includeSecrets=false` but profiles can still contain inline `ssh.proxyPassword` and `ssh.totpSecret` fields. Those fields could be serialized despite a non-secret export request.
+
+#### Evidence
+
+The fix redacts `ProxyPassword` and `TOTPSecret` for non-secret exports in both API and storage layers.
+
+#### Attack Scenario
+
+A user creates a plain profile export believing secrets are excluded. The exported JSON contains proxy credentials or TOTP secrets that are then shared, backed up, or stored insecurely.
+
+#### Impact
+
+Credential leakage and potential 2FA bypass for affected profiles.
+
+#### Recommendation
+
+Redact inline secret fields whenever `includeSecrets=false`. Prefer encrypted export for any export that intentionally includes secrets.
+
+#### Safer Example
+
+Implemented `redactProfileSecrets(...)` in storage and API packages.
+
+#### Suggested Tests
+
+Added:
+
+- `TestExportProfilesRedactsInlineSSHSecrets`
+- `TestRedactProfileSecretsClearsInlineSSHSecrets`
+
+#### References
+
+- CWE-200: Exposure of Sensitive Information.
+- OWASP ASVS 8.3: sensitive data protection.
+
+#### Assumptions / Limitations
+
+The encrypted export path intentionally includes selected profile data and is password-protected.
+
+### Finding ID: SEC-007
+
+#### Title
+
+`golang.org/x/crypto` vulnerable in reachable SSH code
+
+#### Severity
+
+High
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `go.mod`, `golang.org/x/crypto`, now fixed at line 14.
+- `go.mod`, indirect `golang.org/x/sys`, now updated at line 45.
+- Reachable SSH code in `internal/sshclient`, `internal/vncclient`, `internal/sftpclient`.
+
+#### Description
+
+`govulncheck` reported seven reachable vulnerabilities in `golang.org/x/crypto@v0.51.0`, including SSH DoS/panic issues, FIDO/U2F security-key interaction bypass risk, and SSH agent forwarding constraint handling issues.
+
+#### Evidence
+
+`govulncheck` identified GO-2026-5033, GO-2026-5020, GO-2026-5019, GO-2026-5018, GO-2026-5017, GO-2026-5013, and GO-2026-5006 as reachable before the update. The dependency is now `v0.52.0`, and rerun output reports: "No vulnerabilities found. Your code is affected by 0 vulnerabilities."
+
+#### Attack Scenario
+
+A malicious or compromised SSH server, SSH agent, key material, or protocol peer triggers vulnerable SSH library behavior during connection, channel use, key parsing, or agent forwarding.
+
+#### Impact
+
+Possible client panic, denial of service, weakened security-key interaction, or agent forwarding constraint mishandling depending on the CVE path.
+
+#### Recommendation
+
+Keep `golang.org/x/crypto` at or above `v0.52.0` and run `govulncheck` in CI.
+
+#### Safer Example
+
+Implemented: `go get golang.org/x/crypto@v0.52.0`.
+
+#### Suggested Tests
+
+Ran `govulncheck` and `go test ./...`.
+
+#### References
+
+- https://pkg.go.dev/vuln/GO-2026-5033
+- https://pkg.go.dev/vuln/GO-2026-5020
+- https://pkg.go.dev/vuln/GO-2026-5019
+- https://pkg.go.dev/vuln/GO-2026-5018
+- https://pkg.go.dev/vuln/GO-2026-5017
+- https://pkg.go.dev/vuln/GO-2026-5013
+- https://pkg.go.dev/vuln/GO-2026-5006
+
+#### Assumptions / Limitations
+
+`govulncheck` also noted vulnerabilities in required modules that are not called by this code.
+
+### Finding ID: SEC-008
+
+#### Title
+
+`esbuild` dev dependency matched current npm advisory
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `frontend/package.json`, `esbuild`, now fixed at line 22.
+- `frontend/package-lock.json`.
+
+#### Description
+
+`npm audit` reported GHSA-67mh-4wv8-2f99 for `esbuild <=0.24.2`: any website could send requests to the dev server and read responses under affected versions.
+
+#### Evidence
+
+The frontend previously resolved `esbuild@0.24.2`. It now uses `^0.28.0`, and `npm audit --json` reports zero vulnerabilities.
+
+#### Attack Scenario
+
+During local development, a malicious website could interact with the esbuild dev server and read responses if a developer runs an affected dev server.
+
+#### Impact
+
+Possible local development data exposure.
+
+#### Recommendation
+
+Use a fixed esbuild release and keep npm audit in CI.
+
+#### Safer Example
+
+Implemented: `npm install esbuild@0.28.0`.
+
+#### Suggested Tests
+
+Ran `npm audit --json` and `npm run build`.
+
+#### References
+
+- https://github.com/advisories/GHSA-67mh-4wv8-2f99
+
+#### Assumptions / Limitations
+
+This is a devDependency, so production exploitability is lower than runtime dependencies.
+
+### Finding ID: SEC-009
+
+#### Title
+
+Large local file upload paths remain memory-heavy
+
+#### Severity
+
+Low
+
+#### Confidence
+
+Medium
+
+#### Affected Files / Components
+
+- `frontend/src/js/terminal.js`, dropped-file paste/upload flows.
+- `internal/api/api.go`, `SFTPUploadData`.
+
+#### Description
+
+Some upload paths read whole files into memory and send base64 payloads to Go before uploading. This can be expensive for very large local files.
+
+#### Evidence
+
+`SFTPUploadData` decodes the entire base64 payload before calling session upload. The frontend drag/drop paste path also reads file contents into strings.
+
+#### Attack Scenario
+
+A local user or compromised renderer submits very large files, causing high memory use and potential application unresponsiveness.
+
+#### Impact
+
+Local denial of service.
+
+#### Recommendation
+
+Add size limits for paste-as-text, prefer path-based streaming upload for large files, and surface user-facing warnings for files above a threshold.
+
+#### Safer Example
+
+Use file path streaming upload where possible and reject in-memory uploads above a configured maximum.
+
+#### Suggested Tests
+
+Add boundary tests for maximum accepted in-memory upload size and UI tests for large-file warnings.
+
+#### References
+
+- CWE-400: Uncontrolled Resource Consumption.
+
+#### Assumptions / Limitations
+
+This is primarily local/user-assisted. It was left open to avoid changing UX and transfer semantics during the security fix pass.
+
+### Finding ID: SEC-010
+
+#### Title
+
+Direct VNC remains unencrypted by protocol choice
+
+#### Severity
+
+Low
+
+#### Confidence
+
+Medium
+
+#### Affected Files / Components
+
+- `internal/vncclient/vncclient.go`, direct TCP VNC mode.
+- VNC profile settings.
+
+#### Description
+
+Direct VNC connections use raw TCP to the VNC server. VNC is commonly unencrypted unless tunneled or separately protected.
+
+#### Evidence
+
+The direct branch calls `net.DialTimeout` to the VNC endpoint. SSH tunnel mode is available and now host-key verified.
+
+#### Attack Scenario
+
+On an untrusted network, direct VNC traffic may expose screen contents or credentials depending on server configuration.
+
+#### Impact
+
+Sensitive remote desktop data exposure.
+
+#### Recommendation
+
+Warn users before direct VNC connections and prefer SSH tunnel mode by default.
+
+#### Safer Example
+
+Default new VNC profiles to SSH tunnel where feasible, or show an explicit "unencrypted direct VNC" warning.
+
+#### Suggested Tests
+
+Add UI tests that direct VNC profiles show a warning before connection.
+
+#### References
+
+- OWASP ASVS 9.1: communications security.
+
+#### Assumptions / Limitations
+
+Some VNC servers may provide their own encryption; this audit did not test remote server configurations.
+
+## 7. Denial-of-Service Review
+
+Fixed:
+
+- Updated `golang.org/x/crypto` to resolve reachable SSH panic/deadlock/DoS vulnerabilities.
+- Added random-token access control to the local VNC WebSocket proxy, reducing local cross-origin abuse.
+
+Reviewed and not changed:
+
+- HTTP clients for GitHub and update checks use finite timeouts.
+- SSH/Telnet/RAW connection setup uses timeouts.
+- VNC WebSocket bridge is intentionally long-lived and uses no read/write timeout.
+- Large in-memory file upload/paste paths remain a local DoS risk; see SEC-009.
+
+## 8. Dependency and Supply-Chain Review
+
+Checks run:
+
+- `govulncheck`: fixed reachable `golang.org/x/crypto` vulnerabilities by updating to `v0.52.0`; rerun found zero reachable vulnerabilities.
+- `npm audit --json`: fixed `esbuild` advisory by updating to `0.28.0`; rerun found zero vulnerabilities.
+- `npm run build`: passed after dependency update.
+
+Notes:
+
+- `xterm` packages are deprecated upstream in favor of `@xterm/*`, but no current audit advisory was reported in this run.
+- `go.mod` still has transitive modules with vulnerabilities that `govulncheck` reports as not called by this code.
+
+## 9. Secrets and Sensitive Data Review
+
+Fixed:
+
+- Non-secret profile export now redacts inline `ProxyPassword` and `TOTPSecret`.
+- SSH host-key verification now protects credential submission from basic MITM paths.
+
+Reviewed:
+
+- Vault uses Argon2id and AES-256-GCM with random salts/nonces.
+- Vault file is written with `0600` permissions and store directories with `0700`.
+- OS keychain is preferred where available.
+
+Residual:
+
+- Secret values still exist in process memory while sessions need them.
+- Proxy password is still present in profile model state when entered inline.
+
+## 10. Authentication and Authorisation Review
+
+Fixed:
+
+- SSH, jump host, and VNC-over-SSH authentication now has host authenticity checks before credential use.
+- SSH host-key prompt responses are request-correlated.
+
+Reviewed:
+
+- SSH/TOTP flows use profile-specific secret callbacks.
+- Agent forwarding is explicit profile configuration.
+- Known-host policies include strict, ask, accept-new, and insecure.
+
+Residual:
+
+- `HostKeyInsecure` remains available for user-selected insecure connections.
+
+## 11. Input Validation and Output Encoding Review
+
+Fixed:
+
+- SSH key names now reject traversal and nested path separators.
+- Update metadata is rendered with DOM APIs instead of string-built HTML.
+- Non-secret export redacts inline secret fields.
+
+Reviewed:
+
+- SQL operations use parameterized queries.
+- Profile validation checks host, port, username, protocol-specific fields, and port-forwarding basics.
+- Frontend frequently uses `textContent` or `escapeHtml`; remaining `innerHTML` static templates should still be reviewed during future frontend hardening.
+
+## 12. Infrastructure and Deployment Review
+
+Reviewed:
+
+- Wails app binds Go services directly to the renderer. This makes frontend XSS more impactful than in a browser-only app.
+- Build scripts use `set -euo pipefail`.
+- Update checking is opt-in and does not auto-install binaries.
+
+Residual:
+
+- No CI configuration was present in the reviewed file list, so dependency scanning is not currently enforced by repository automation.
+
+## 13. Logging, Monitoring, and Error Handling Review
+
+Reviewed:
+
+- Audit logger records profile create/update/delete, connection events, secret access, import/export.
+- Errors are generally returned to the frontend with enough context for troubleshooting.
+
+Residual:
+
+- Some error messages include file paths, which is acceptable for a local desktop tool but should be considered if telemetry is later added.
+
+## 14. Test Coverage and Security Regression Gaps
+
+Added tests:
+
+- API SSH key path validation and export redaction.
+- Session host-key callback storage and strict rejection behavior.
+- Jump-host host-key callback propagation.
+- Storage export redaction.
+- VNC proxy token generation.
+
+Remaining gaps:
+
+- No frontend unit test harness for DOM injection regressions.
+- No integration test for full Wails host-key prompt round trip.
+- No VNC WebSocket integration test verifying token-only connection behavior.
+- No large-file upload boundary tests.
+
+## 15. Prioritised Remediation Plan
+
+Immediate:
+
+- Keep the fixes in this audit and ensure they are merged.
+- Add dependency scanning to CI: `govulncheck ./...` and `npm audit --audit-level=moderate`.
+
+Short-term:
+
+- Add a frontend test harness for update UI and other dynamic DOM surfaces.
+- Add direct VNC warning UX and default to SSH tunnel where possible.
+- Add explicit in-memory upload size limits.
+
+Medium-term:
+
+- Expose host-key policy for VNC SSH tunnels instead of always using ask mode.
+- Review all Wails-exposed methods under a compromised-renderer threat model.
+- Migrate deprecated `xterm` packages to maintained `@xterm/*` packages.
+
+Long-term:
+
+- Consider capability gating or confirmation for high-risk renderer-callable APIs such as file deletion, SSH key deletion, local shell selection, and profile import/export.
+- Add signed update metadata if self-hosted update manifests become a production channel.
+
+## 16. False Positives / Needs Manual Verification
+
+- Wails/noVNC Origin behavior in a packaged app should be manually verified. Tokenized VNC WebSocket paths are in place, but Origin policy may still be tightened later.
+- Direct VNC encryption depends on remote VNC server configuration and network placement.
+- `HostKeyInsecure` is intentionally user-configurable; confirm UI wording makes the risk clear.
+- Large-file memory usage thresholds need product decisions before enforcement.
+
+## 17. Final Notes
+
+Fix mode completed with code changes, tests, and dependency updates. The strongest residual concern is the general Wails threat model: a frontend XSS can call powerful local backend APIs. This audit fixed the confirmed dynamic update UI injection path and several backend trust-boundary issues, but future work should continue reducing string-built HTML and adding capability checks around sensitive local operations.

Makefile

@@ -1,69 +0,0 @@
-.PHONY: all build dev clean test test-cover lint install deps frontend-deps run package release help
-
-# Resolve the Wails binary. Prefer wails on PATH; fall back to GOPATH/bin.
-WAILS := $(or $(shell which wails 2>/dev/null),$(shell go env GOPATH)/bin/wails)
-VERSION := $(shell git describe --tags --abbrev=0 2>/dev/null || echo dev)-$(shell git rev-parse --short HEAD 2>/dev/null || echo unknown)
-LD_UPDATE_URL := $(if $(NEXUS_UPDATE_URL),-X github.com/andydixon/nexus/internal/api.appUpdateURL=$(NEXUS_UPDATE_URL),)
-
-# Default target
-all: build
-
-# Install all dependencies
-deps: frontend-deps
-	go mod download
-
-# Install frontend dependencies
-frontend-deps:
-	cd frontend && npm install
-
-# Development mode with hot reload
-dev: deps
-	$(WAILS) dev
-
-# Production build
-build: deps
-	$(WAILS) build -ldflags "-s -w -X github.com/andydixon/nexus/internal/api.appVersion=$(VERSION) $(LD_UPDATE_URL)"
-
-# Run tests
-test:
-	go test ./... -v -count=1
-
-# Run tests with coverage
-test-cover:
-	go test ./... -v -count=1 -coverprofile=coverage.out
-	go tool cover -html=coverage.out -o coverage.html
-
-# Clean build artefacts
-clean:
-	rm -rf build/bin
-	rm -rf frontend/node_modules
-	rm -rf frontend/src/js/lib
-	rm -rf frontend/src/css/lib
-	go clean -testcache
-
-# Lint (requires golangci-lint)
-lint:
-	golangci-lint run ./...
-
-# Package for distribution
-package: build
-	@echo "Binary built at build/bin/"
-
-# Build and package release artefacts for all platforms
-release:
-	./release.sh
-
-# Help
-help:
-	@echo "Nexus Terminal — Build Targets"
-	@echo ""
-	@echo "  make deps          — Install all dependencies"
-	@echo "  make dev           — Run in development mode with hot reload"
-	@echo "  make build         — Production build"
-	@echo "  make test          — Run tests"
-	@echo "  make test-cover    — Run tests with coverage report"
-	@echo "  make clean         — Clean build artefacts"
-	@echo "  make lint          — Run linter (requires golangci-lint)"
-	@echo "  make package       — Build and package for distribution"
-	@echo "  make release       — Build multi-platform release artefacts"
-	@echo "  make help          — Show this help"

README.md

@@ -1,26 +1,29 @@
 # Nexus Terminal
 
-**A desktop client for SSH, Telnet, RAW TCP, and GitHub — with secure credential handling and a focused, multi-session workflow.**
+**A native desktop client for SSH, Telnet, RAW TCP, Serial, VNC, RDP, IRC, GitHub and local terminals — with secure credential handling and a focused, multi-session workflow.**
 
-Nexus Terminal helps you manage many connections at once, keep terminal work organised, and move files with confidence.
+Nexus Terminal helps you manage many connections at once, keep terminal work organised, and move files with confidence. It is a single Rust application with no webview, so it starts quickly and stays responsive under heavy terminal output.
 
 ## Highlights
 
-- SSH, Telnet, RAW TCP, and GitHub sessions in one app
-- Tabbed sessions with split panes, pinning, and reordering
-- SFTP browser with drag-and-drop uploads and a directory picker
-- Disconnected overlay with one-click reconnect
-- Broadcast input, snippets, and terminal search
-- Session recording and playback
-- Secure credential storage with OS keychain and encrypted vault fallback
+- SSH, Telnet, RAW TCP, Serial, VNC, RDP, IRC, GitHub and local terminal sessions in one app
+- Tabbed sessions with split panes, pinning and drag-to-reorder
+- SFTP browser with drag-and-drop uploads and a permission-aware directory picker
+- SSH jump hosts, SOCKS5/HTTP proxies, local and remote port forwards, agent forwarding and TOTP auto-fill
+- Serial consoles with full line settings (baud, data bits, parity, stop bits, flow control)
+- Native VNC and RDP viewers; RDP with NLA, certificate pinning, and SOCKS5/HTTP proxy or SSH tunnel routes
+- Disconnected overlay with one-click reconnect, and auto-reconnect with backoff
+- Broadcast input, snippets, trigger rules and terminal search
+- Session recording (asciicast v2) and playback
+- Secure credential storage with the OS keychain first and an encrypted vault fallback
 
 ## Quick start
 
 1. Launch Nexus Terminal.
-2. Click **New** in the sidebar and create a connection profile.
-3. Click **Connect** to open a session in a new tab.
+2. Click **+** at the bottom of the sidebar (or press **Cmd+N** / **Ctrl+N**) and create a connection profile.
+3. Click **Create & Connect** to save it and open a session in a new tab. Afterwards, click the profile in the sidebar to connect.
 
-Prefer a one-off session? Use **Cmd+Shift+Q** / **Ctrl+Shift+Q** to quick connect.
+Prefer a one-off session? Use **Cmd+Shift+Q** / **Ctrl+Shift+Q** to quick connect, or click **Local Machine** in the sidebar for a local shell.
 
 If a session drops, use the **Reconnect** button in the disconnected overlay.
 
@@ -29,26 +32,38 @@ If a session drops, use the **Reconnect** button in the disconnected overlay.
 - Product overview: [docs/overview.md](docs/overview.md)
 - Quick start (shareable): [docs/quick-start.md](docs/quick-start.md)
 - User manual: [docs/user-manual.md](docs/user-manual.md)
+- Illustrated user guide (PDF): [docs/guide/nexus-guide.pdf](docs/guide/nexus-guide.pdf), built from LaTeX in [docs/guide](docs/guide) (`make` there; `tools/screenshots.sh` regenerates the screenshots)
 - Build and release: [docs/build-and-release.md](docs/build-and-release.md)
 
 ## Keyboard shortcuts
 
 All shortcuts use **Cmd** on macOS and **Ctrl** on Windows/Linux.
 
-| macOS Shortcut    | Windows/Linux Shortcut | Action                      |
-| ----------------- | ---------------------- | --------------------------- |
-| Cmd + K           | Ctrl + K               | Open command palette        |
-| Cmd + N           | Ctrl + N               | New connection              |
-| Cmd + W           | Ctrl + W               | Close current tab           |
-| Cmd + Tab         | Ctrl + Tab             | Next tab                    |
-| Cmd + Shift + Tab | Ctrl + Shift + Tab     | Previous tab                |
-| Cmd + 1–9         | Ctrl + 1–9             | Switch to tab by number     |
-| Cmd + ,           | Ctrl + ,               | Open settings               |
-| Cmd + F           | Ctrl + F               | Find in terminal            |
-| Cmd + Shift + D   | Ctrl + Shift + D       | Split pane vertically       |
-| Cmd + Shift + E   | Ctrl + Shift + E       | Split pane horizontally     |
-| Cmd + Shift + R   | Ctrl + Shift + R       | Toggle session recording    |
-| Cmd + Shift + B   | Ctrl + Shift + B       | Toggle broadcast input mode |
-| Cmd + Shift + S   | Ctrl + Shift + S       | Open snippet library        |
-| Cmd + Shift + Q   | Ctrl + Shift + Q       | Quick connect               |
-| F11               | F11                    | Toggle fullscreen           |
+| macOS Shortcut    | Windows/Linux Shortcut | Action                           |
+| ----------------- | ---------------------- | -------------------------------- |
+| Cmd + K           | Ctrl + K               | Open command palette             |
+| Cmd + N           | Ctrl + N               | New connection                   |
+| Cmd + W           | Ctrl + W               | Close current tab                |
+| Cmd + Tab         | Ctrl + Tab             | Next tab                         |
+| Cmd + Shift + Tab | Ctrl + Shift + Tab     | Previous tab                     |
+| Cmd + 1–9         | Ctrl + 1–9             | Switch to tab by number          |
+| Cmd + ,           | Ctrl + ,               | Open settings                    |
+| Cmd + F           | Ctrl + F               | Find in terminal                 |
+| Cmd + Shift + D   | Ctrl + Shift + D       | Split pane right (side by side)  |
+| Cmd + Shift + E   | Ctrl + Shift + E       | Split pane down (top and bottom) |
+| Cmd + Shift + R   | Ctrl + Shift + R       | Toggle session recording         |
+| Cmd + Shift + B   | Ctrl + Shift + B       | Toggle broadcast input mode      |
+| Cmd + Shift + S   | Ctrl + Shift + S       | Open snippet library             |
+| Cmd + Shift + Q   | Ctrl + Shift + Q       | Quick connect                    |
+| F11               | F11                    | Toggle fullscreen                |
+
+## Building from source
+
+Nexus Terminal is a Rust workspace in `rust/`. With [rustup](https://rustup.rs) installed:
+
+```bash
+cd rust
+cargo run --release
+```
+
+See [docs/build-and-release.md](docs/build-and-release.md) for platform prerequisites, tests and release packaging.

audits/20260615-1934-functionalityNextSteps.md

@@ -0,0 +1,126 @@
+# Functionality and Next Steps Report
+
+## 1. Executive Summary
+
+This fix-mode audit improved immediate security and robustness around profile validation, imports, drag-drop upload, frontend encoding, dependencies, and release reproducibility.
+
+The most useful next work is to turn these fixes into durable product quality: add frontend interaction tests, make large file upload streaming and consistent, warn users about intentionally insecure protocol choices, and strengthen release provenance.
+
+## 2. Current Functional Risks
+
+Direct VNC can still be used without SSH tunnelling. That is valid for trusted networks, but the UI should make the risk visible when profiles are saved or connected.
+
+Drag-drop SFTP upload is now capped at 25 MiB because it still uses an in-memory browser-to-Go base64 path. Larger files should use the existing native SFTP upload flow or a future streaming drag-drop implementation.
+
+Profile import now rejects malformed or unsafe profiles before storage. That is safer, but older third-party exports with missing defaults may need a clearer import error UI or a migration/repair preview.
+
+RAW session history and recordings can still grow over long sessions. Users need limits, retention controls, and clear storage management.
+
+## 3. Code Quality Improvements
+
+Profile validation is now centralized enough for create/update/import, but profile normalization is still split between frontend defaults, Go defaults, and import-time cleanup. A schema-versioned import normalizer would make future protocol additions safer.
+
+Frontend still has many `innerHTML` templates. Some are static or escaped, but a small helper pattern for safe modal construction would reduce future XSS mistakes.
+
+Release scripts and CI now use pinned Wails and `npm ci`; follow-up work should avoid duplicate release logic between `build.sh`, `release.sh`, and GitHub Actions.
+
+## 4. Frontend Interaction and Error-Handling Improvements
+
+Add Wails/browser interaction tests for:
+
+- Dropping a file with HTML metacharacters in its filename.
+- Dropping a file over 25 MiB.
+- Importing malformed and oversized profile bundles.
+- Saving GitHub profiles with HTTP and HTTPS API base URLs.
+- Creating direct VNC profiles and seeing a warning.
+
+Improve import UX by showing which profile entry failed validation without exposing secret values.
+
+## 5. Testing Roadmap
+
+Immediate tests to add:
+
+- Frontend DOM regression for file-drop title rendering.
+- API tests for successful valid GitHub Enterprise HTTPS profile creation.
+- Import tests for mixed valid/invalid profile arrays.
+
+Short-term tests:
+
+- End-to-end Wails smoke tests for create profile, connect prompt flow, import/export, SFTP upload, and VNC tunnel setup.
+- Load tests for large SFTP directories, RAW captures, and recordings.
+- CI security job with `npm audit`, govulncheck, and secret scanning.
+
+Longer-term tests:
+
+- Release workflow dry-run or artifact validation tests.
+- Migration tests for profile schema changes.
+
+## 6. Recommended New Functionality
+
+Add a direct-VNC safety warning and a per-profile “prefer SSH tunnel” nudge.
+
+Add streaming drag-drop SFTP upload for larger files, or route drag-drop files above 25 MiB into the native upload flow.
+
+Add import preview: list profile names, protocols, validation warnings, and duplicate handling before writing.
+
+Add recording retention settings: max recording size, max age, and one-click cleanup.
+
+Add security diagnostics in settings: dependency check status, known-host summary, direct insecure profile count, and last audit-log events.
+
+## 7. Next-Level Opportunities
+
+Release hardening:
+
+- Sign and notarize release artifacts where platform-appropriate.
+- Publish checksums and provenance.
+- Pin or cache dependency sources in CI.
+
+Observability:
+
+- Add structured non-sensitive debug logs for import rejection, update checks, VNC proxy lifecycle, and SFTP transfer failures.
+- Add audit entries for validation failures that indicate suspicious imports, without storing payload contents.
+
+Developer experience:
+
+- Consolidate release/build dependency resolution into one reusable script.
+- Add a frontend lint rule or custom check for unsafe `innerHTML` with dynamic values.
+
+Accessibility/product quality:
+
+- Ensure modal error states are keyboard reachable and announced.
+- Add clearer status messages for blocked uploads and import validation failures.
+
+## 8. Prioritised Action Plan
+
+Immediate:
+
+- Add direct VNC warning copy and tests.
+- Add frontend file-drop XSS and oversize tests.
+- Add CI jobs for `go test ./...`, `npm run build`, `npm audit`, and govulncheck.
+
+Short-term:
+
+- Replace deprecated `xterm` packages with maintained `@xterm/*` packages.
+- Build import preview and validation repair UI.
+- Add recording and RAW capture storage limits.
+
+Medium-term:
+
+- Implement streaming drag-drop upload.
+- Add release signing, checksums, and provenance.
+- Add schema-versioned profile import/export.
+
+Long-term:
+
+- Build a security/settings dashboard for insecure profiles, known hosts, audit status, and update health.
+- Add comprehensive Wails end-to-end smoke coverage for core workflows.
+
+## 9. Caveats and Validation Needed
+
+The fixes were verified with automated local checks, but not with live Wails UI automation.
+
+The new import validation may reject malformed legacy profiles that were previously accepted. That is intentional for safety, but the UX should help users repair old data.
+
+The 25 MiB drag-drop upload cap is a guardrail, not a final large-file strategy. Streaming support would be the better long-term user experience.
+
+Direct VNC was left open because some users need it on trusted networks; the next step is product warning and safer defaults, not silent removal.

audits/20260615-1934-securityAudit.md

@@ -0,0 +1,752 @@
+# Security Audit Report
+
+## 1. Executive Summary
+
+This fix-mode audit reviewed Nexus Terminal, a Wails desktop client with a Go backend and JavaScript frontend for SSH, Telnet, RAW TCP, VNC, SFTP, GitHub, recordings, local shells, encrypted secrets, and profile import/export.
+
+The highest-risk issues fixed in this run were unsafe profile persistence/import validation, a local DOM XSS trigger in the file-drop modal, memory-exhaustion paths in import and drag-drop upload flows, vulnerable dependency versions, and release tooling that installed unpinned build dependencies. I also removed the stale insecure SSH connection helper so future code cannot silently bypass host-key verification.
+
+Post-fix verification passed: `go test ./...`, focused Go tests, `npm run build`, `npm audit --json`, `go run golang.org/x/vuln/cmd/govulncheck@latest ./...`, `bash -n build.sh release.sh`, and `git diff --check`.
+
+Residual risk remains where users intentionally choose insecure protocols or workflows, especially direct VNC without SSH tunnelling. No high-confidence secrets or private keys were found in the repository search performed during this audit.
+
+## 2. Scope Reviewed
+
+Reviewed code and configuration:
+
+- Go backend under `internal/`: API bindings, sessions, SSH, VNC, SFTP, storage, secrets, export/import, validation, updater, recordings, local shell, GitHub client, raw and telnet clients.
+- Frontend JavaScript under `frontend/src/js`, especially file drop, terminal, settings, GitHub, profile, SFTP, VNC, notification, and import/export flows.
+- Dependency manifests and lockfiles: `go.mod`, `go.sum`, `frontend/package.json`, `frontend/package-lock.json`.
+- Build/release configuration: `build.sh`, `release.sh`, `.github/workflows/release-builds.yml`, `wails.json`.
+- Existing tests under `internal/**/*_test.go`.
+
+Not reviewed with live external testing:
+
+- Real SSH/VNC/GitHub endpoints.
+- Packaged binaries and platform installers.
+- Manual UI testing inside a running Wails app.
+
+## 3. Methodology
+
+I used a two-pass review:
+
+- Attack-surface mapping of Wails API methods, import/export paths, file handling, DOM sinks, dependency/build chain, protocol clients, local proxy behavior, and credential flows.
+- Defensive validation from source and tests, followed by smallest safe fixes with regression tests.
+
+Tools/checks used:
+
+- Static review with `rg`, direct source reads, and line evidence.
+- `go test ./...`.
+- Focused tests for API, storage, export/import, validation, SSH client, and sessions.
+- `npm audit --json`.
+- `npm run build`.
+- `go run golang.org/x/vuln/cmd/govulncheck@latest ./...`.
+- `bash -n build.sh release.sh`.
+- `git diff --check`.
+
+## 4. Risk Rating Method
+
+Severity considered attacker position, exploit preconditions, likely impact, and whether sensitive credentials or code execution could be affected.
+
+- Critical: practical remote compromise or credential disclosure with minimal preconditions.
+- High: credible dependency, credential, or supply-chain compromise.
+- Medium: user-assisted or renderer/local attack that can affect confidentiality, integrity, or availability.
+- Low: hardening, defense-in-depth, or intentionally insecure user-selected modes.
+- Informational: verified area, non-exploitable issue, or test gap.
+
+Confidence is High where source evidence and regression checks directly support the finding.
+
+## 5. Attack Surface Map
+
+Entry points:
+
+- Wails-bound Go API methods in `internal/api/api.go`.
+- Profile create/update/import/export and encrypted `.nexus` imports.
+- Drag-and-drop file upload/paste in `frontend/src/js/terminal.js`.
+- SSH, Telnet, RAW TCP, VNC, SFTP, GitHub API, and local shell sessions.
+- Local VNC WebSocket proxy on loopback.
+- Build/release automation and dependency installation.
+
+Trust boundaries:
+
+- Frontend renderer to Wails API.
+- User-selected/imported local files to backend parsers.
+- Saved/imported profiles to outbound network clients.
+- Remote hosts and GitHub/GitHub Enterprise APIs to frontend rendering.
+- Local filesystem/keychain/vault to application process.
+- CI/release environment to dependency registries and Go module proxy.
+
+Attacker starting positions considered:
+
+- Malicious imported profile bundle.
+- Crafted local file or filename dropped into the terminal.
+- Compromised renderer or malicious frontend input reaching Wails APIs.
+- Network attacker on SSH/VNC/GitHub paths.
+- Dependency registry or release-time supply-chain manipulation.
+
+## 6. Findings Summary Table
+
+| ID | Severity | Confidence | Title | Component | Status |
+|---|---:|---:|---|---|---|
+| SEC-20260615-001 | Medium | High | Profile persistence and imports accepted unsafe or malformed profiles | API, validation, import | Fixed |
+| SEC-20260615-002 | Medium | High | Import and drag-drop upload paths allowed memory exhaustion | Import/export, SFTP upload | Fixed |
+| SEC-20260615-003 | Medium | High | Dropped filenames were rendered through `innerHTML` | Frontend terminal file-drop modal | Fixed |
+| SEC-20260615-004 | Medium | High | Unused SSH helper still defaulted to insecure host-key verification | SSH client | Fixed |
+| SEC-20260615-005 | High | High | Dependency advisories affected `esbuild` and required `x/net` module versions | Dependencies | Fixed |
+| SEC-20260615-006 | Medium | High | Release automation installed unpinned build dependencies | CI/release supply chain | Fixed |
+| SEC-20260615-007 | Low | High | Direct VNC remains unencrypted when SSH tunnelling is disabled | VNC client | Open |
+
+## 7. Detailed Findings
+
+### Finding ID: SEC-20260615-001
+
+#### Title
+
+Profile persistence and imports accepted unsafe or malformed profiles
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/api/api.go`, `CreateProfile`, `UpdateProfile`, `ImportProfiles`, `ImportProfilesEncrypted`, lines 94-131, 715-728, 1176-1189, 1754-1791.
+- `internal/validation/validation.go`, profile, GitHub, and VNC validation, lines 51-140 and 325-410.
+- `internal/storage/store.go`, `ImportProfiles`, lines 365-380.
+
+#### Description
+
+The API comment said profile creation validates input, but the Wails API previously persisted profiles without calling the validation package. Plain JSON import also decoded into `[]*models.Profile` and dereferenced entries without rejecting `null`. A malicious or corrupt import could therefore crash the app or store profiles with unsafe GitHub API base URLs that would later receive a saved or prompted token.
+
+#### Evidence
+
+The fixed code now calls `validation.ValidateProfile` before create/update and validates every imported profile before writing. GitHub API base URLs must be HTTPS unless loopback, must be absolute, and must not include URL credentials. Import strategy and null entries are rejected before persistence.
+
+Regression tests were added in `internal/api/api_test.go` and `internal/storage/storage_test.go`.
+
+#### Attack Scenario
+
+A user imports a profile JSON containing a GitHub profile with `http://evil.example/api/v3` as the API base URL, or a `null` profile entry. Before the fix, malformed data could be saved or crash import handling. If the malicious GitHub profile were later used, the app could send a token to an attacker-controlled endpoint.
+
+#### Impact
+
+Possible token exposure through malicious profile configuration, app crash during import, and fragile persisted state.
+
+#### Recommendation
+
+Validate all Wails-bound persistence inputs and imported profiles before storage. Reject non-HTTPS remote GitHub API URLs and malformed entries.
+
+#### Safer Example
+
+Implemented:
+
+- `CreateProfile` and `UpdateProfile` call `validation.ValidateProfile`.
+- `ValidateGitHubConfig` rejects remote HTTP and URL credentials.
+- Import helpers reject oversized, null, or invalid entries before writes.
+
+#### Suggested Tests
+
+Implemented:
+
+- Unsafe GitHub base URL rejection.
+- Null import entry rejection.
+- Oversized JSON import rejection.
+- Storage-level null import entry rejection.
+- GitHub and VNC validation cases.
+
+#### References
+
+- CWE-20: Improper Input Validation.
+- CWE-200: Exposure of Sensitive Information to an Unauthorized Actor.
+- OWASP API Security Top 10: API3 Broken Object Property Level Authorization / unsafe object properties.
+
+#### Assumptions / Limitations
+
+GitHub Enterprise over non-loopback HTTP is now rejected. If a legitimate deployment needs HTTP, it should be placed behind local loopback or HTTPS.
+
+### Finding ID: SEC-20260615-002
+
+#### Title
+
+Import and drag-drop upload paths allowed memory exhaustion
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/api/api.go`, plain import and SFTP drag-drop upload, lines 715-718 and 1336-1350.
+- `internal/exportimport/exportimport.go`, encrypted import file read, lines 37 and 131-144.
+- `frontend/src/js/terminal.js`, drag-drop file upload cap, lines 10 and 829-849.
+
+#### Description
+
+Several local file paths loaded attacker-controlled or user-selected content fully into memory without a size cap. Plain profile JSON import accepted arbitrary string size from the renderer. Encrypted `.nexus` import used `os.ReadFile` on the selected path. Drag-drop SFTP upload read each browser `File` into an `ArrayBuffer`, converted it to base64, and sent it to the backend, where it was decoded into another byte slice.
+
+#### Evidence
+
+The fixed code adds:
+
+- 5 MiB cap for plain profile JSON import.
+- 10 MiB cap for encrypted `.nexus` import files.
+- 25 MiB frontend and backend caps for inline drag-drop SFTP uploads.
+
+Regression tests cover oversized plain import, encrypted import, and backend upload payload rejection.
+
+#### Attack Scenario
+
+A user drops or imports a very large crafted file. Before the fix, the renderer and backend could allocate multiple full copies, causing high memory pressure or an app crash.
+
+#### Impact
+
+Local denial of service against the desktop application.
+
+#### Recommendation
+
+Keep bounded inline payload paths and prefer streaming APIs for larger transfers. The existing native SFTP upload path streams local files and should remain the recommended path for large uploads.
+
+#### Safer Example
+
+Implemented size checks before decode/read where practical:
+
+- `base64.StdEncoding.DecodedLen` guard before decoding drag-drop upload payloads.
+- `os.Stat` size check before encrypted import `os.ReadFile`.
+
+#### Suggested Tests
+
+Implemented:
+
+- `TestImportProfilesRejectsOversizedJSON`.
+- `TestDecryptRejectsOversizedFile`.
+- `TestSFTPUploadDataRejectsOversizedPayloadBeforeSessionLookup`.
+
+#### References
+
+- CWE-400: Uncontrolled Resource Consumption.
+- OWASP ASVS 12.4: file and resource limits.
+
+#### Assumptions / Limitations
+
+The caps are conservative application-level limits. Larger profile bundles or drag-drop uploads now require a streaming implementation or the existing native SFTP upload flow.
+
+### Finding ID: SEC-20260615-003
+
+#### Title
+
+Dropped filenames were rendered through `innerHTML`
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `frontend/src/js/terminal.js`, file-drop modal, lines 720-742.
+
+#### Description
+
+The file-drop modal interpolated the dropped filename into an `innerHTML` template. Local files can have names containing HTML metacharacters. In a Wails desktop app, DOM script execution is higher impact than a normal static page because the renderer can call privileged Wails APIs.
+
+#### Evidence
+
+The fixed modal escapes the file-drop title with `escapeHtml(title)` before injecting it into the template.
+
+#### Attack Scenario
+
+A user downloads or receives a file with a crafted name such as an HTML tag with an event handler, then drops it into a terminal. Before the fix, the modal could parse the filename as markup.
+
+#### Impact
+
+Potential renderer-side script execution and access to Wails-bound APIs from malicious DOM content.
+
+#### Recommendation
+
+Do not put user-controlled strings into `innerHTML`. Use `textContent` or escape before insertion.
+
+#### Safer Example
+
+Implemented `escapeHtml(title)` in the file-drop modal.
+
+#### Suggested Tests
+
+Add a frontend interaction test that drops a file named with `<img ...>`-style metacharacters and asserts the modal text is rendered literally. Manual Wails/browser verification was not run in this audit.
+
+#### References
+
+- CWE-79: Improper Neutralization of Input During Web Page Generation.
+- OWASP ASVS 5.3: output encoding.
+
+#### Assumptions / Limitations
+
+This fix covers the reviewed file-drop title sink. Other `innerHTML` templates were spot-checked; future work should add an automated DOM-sink lint or test pass.
+
+### Finding ID: SEC-20260615-004
+
+#### Title
+
+Unused SSH helper still defaulted to insecure host-key verification
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/sshclient/sshclient.go`, `Connect`, lines 72-75.
+- `internal/sshclient/sshclient_test.go`, regression test, lines 12-19.
+
+#### Description
+
+Current production session code uses explicit host-key callbacks, and no remaining reviewed SSH/VNC path calls `ssh.InsecureIgnoreHostKey`. However, the internal `sshclient.Connect` helper still defaulted to an insecure host-key callback. That made future misuse easy.
+
+#### Evidence
+
+The helper now fails closed and instructs callers to use `ConnectWithHostKeyCallback`. `rg` found no remaining `InsecureIgnoreHostKey` references after the change.
+
+#### Attack Scenario
+
+A future feature calls the convenience method instead of `ConnectWithHostKeyCallback`. Before the fix, that new path would silently accept any SSH host key.
+
+#### Impact
+
+Potential SSH machine-in-the-middle exposure if the helper were reused.
+
+#### Recommendation
+
+Keep host-key policy explicit on every SSH path. Do not provide insecure convenience APIs in internal packages.
+
+#### Safer Example
+
+Implemented: `Connect` returns `sshclient: host key callback is required`.
+
+#### Suggested Tests
+
+Implemented `TestConnectRequiresHostKeyCallback`.
+
+#### References
+
+- CWE-295: Improper Certificate Validation, analogous to SSH host-key validation.
+- OWASP ASVS 9.1.2: server authenticity validation.
+
+#### Assumptions / Limitations
+
+This is a preventive fix. The reviewed production paths already used explicit callbacks.
+
+### Finding ID: SEC-20260615-005
+
+#### Title
+
+Dependency advisories affected `esbuild` and required `x/net` module versions
+
+#### Severity
+
+High
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `frontend/package.json`, `esbuild`, line 22.
+- `frontend/package-lock.json`, `esbuild` and platform packages.
+- `go.mod`, `golang.org/x/net`, line 15.
+- `go.sum`.
+
+#### Description
+
+`npm audit` reported `esbuild 0.28.0` affected by a high-severity advisory and a low-severity advisory. `govulncheck -show verbose` reported six vulnerabilities in required `golang.org/x/net v0.54.0` modules, though no reachable symbols were called by this code.
+
+#### Evidence
+
+The fixed versions are:
+
+- `esbuild` bumped to `^0.28.1`.
+- `golang.org/x/net` bumped to `v0.55.0`.
+
+Post-fix `npm audit --json` reports zero vulnerabilities and `govulncheck` reports `No vulnerabilities found.`
+
+#### Attack Scenario
+
+For `esbuild`, a compromised or manipulated package installation environment could exploit known build-tool weaknesses. For `x/net`, future code changes could start calling vulnerable symbols if the module stayed on an affected version.
+
+#### Impact
+
+Supply-chain compromise risk during build/development and latent dependency risk.
+
+#### Recommendation
+
+Keep audited dependency patch versions current and include `npm audit` and `govulncheck` in regular release checks.
+
+#### Safer Example
+
+Implemented package/module upgrades and lockfile updates.
+
+#### Suggested Tests
+
+Implemented verification:
+
+- `npm audit --json`.
+- `go run golang.org/x/vuln/cmd/govulncheck@latest ./...`.
+- `go test ./...`.
+- `npm run build`.
+
+#### References
+
+- CWE-494: Download of Code Without Integrity Check.
+- CWE-1104: Use of Unmaintained Third Party Components.
+- Go vulnerability database advisories for `golang.org/x/net`.
+- GitHub Advisory Database for `esbuild`.
+
+#### Assumptions / Limitations
+
+The `x/net` advisories were not reachable before the bump, according to govulncheck. The upgrade removes the latent module-level finding anyway.
+
+### Finding ID: SEC-20260615-006
+
+#### Title
+
+Release automation installed unpinned build dependencies
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `.github/workflows/release-builds.yml`, Wails and npm install steps, lines 66-70.
+- `release.sh`, Wails and npm install logic, lines 76-99.
+
+#### Description
+
+The release workflow installed the Wails CLI with `@latest` and used `npm install` rather than the lockfile-enforcing `npm ci`. Local release scripting also instructed or performed unpinned dependency installation in some paths.
+
+#### Evidence
+
+The fixed workflow installs the Wails CLI at the version resolved from `go.mod` and uses `npm ci`. `release.sh` now installs the pinned Wails CLI version from `go.mod` when needed and uses `npm ci` when `frontend/package-lock.json` exists.
+
+#### Attack Scenario
+
+A release build runs after a compromised or breaking upstream release, or after lockfile drift. Before the fix, release outputs could include unreviewed dependency changes.
+
+#### Impact
+
+Build reproducibility loss and supply-chain risk in release artifacts.
+
+#### Recommendation
+
+Use pinned module versions and lockfile-enforced installs in CI/release paths.
+
+#### Safer Example
+
+Implemented:
+
+- `go install ...@$(go list -m -f '{{.Version}}' github.com/wailsapp/wails/v2)`.
+- `npm ci` in CI and release script.
+
+#### Suggested Tests
+
+Implemented:
+
+- `bash -n build.sh release.sh`.
+- Frontend build after `npm ci`.
+
+#### References
+
+- SLSA build integrity principles.
+- CWE-494.
+
+#### Assumptions / Limitations
+
+The workflow still allows network dependency retrieval during CI. Stronger controls would include dependency caching, provenance, and artifact signing.
+
+### Finding ID: SEC-20260615-007
+
+#### Title
+
+Direct VNC remains unencrypted when SSH tunnelling is disabled
+
+#### Severity
+
+Low
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/sessions/manager.go`, direct VNC branch, lines 1012-1062.
+- `internal/vncclient/vncclient.go`, direct TCP dial, lines 139-144.
+
+#### Description
+
+When VNC SSH tunnelling is disabled, the client makes a direct TCP VNC connection. Classic VNC deployments often provide weak or no transport encryption.
+
+#### Evidence
+
+The VNC client intentionally supports both SSH-tunnelled and direct modes. The direct branch uses `net.DialTimeout` to the VNC address.
+
+#### Attack Scenario
+
+A user connects directly to VNC over an untrusted network. A network attacker observes or tampers with remote desktop traffic, depending on the VNC server's negotiated security type.
+
+#### Impact
+
+Potential confidentiality and integrity loss for remote desktop sessions.
+
+#### Recommendation
+
+Keep direct VNC available for trusted networks, but clearly warn users when SSH tunnelling is disabled and consider requiring explicit confirmation for saved direct-VNC profiles.
+
+#### Safer Example
+
+Prefer enabling `vnc.sshTunnel` and verifying the SSH host key for the tunnel host.
+
+#### Suggested Tests
+
+Add a UI test that direct VNC profiles show a warning, and an integration test that tunnelled VNC requires a host-key callback.
+
+#### References
+
+- OWASP ASVS 9.1: secure channel requirements.
+
+#### Assumptions / Limitations
+
+This was not changed in this run because direct VNC can be a deliberate user choice for isolated networks.
+
+## 8. Blackhat-Style Abuse Paths
+
+Path A: malicious profile import to token exfiltration, now blocked.
+
+1. Provide a profile bundle with a GitHub API base URL pointing to attacker infrastructure.
+2. User imports and connects.
+3. App prompts for or retrieves a token and sends it to the configured endpoint.
+4. Defensive breakpoints now added: profile validation, HTTPS requirement for remote GitHub APIs, import validation before storage.
+
+Path B: crafted dropped filename to renderer script execution, now blocked.
+
+1. User receives a file with HTML metacharacters in the filename.
+2. User drops it into a terminal.
+3. Filename is rendered in the file-drop modal.
+4. Defensive breakpoint now added: title is escaped before `innerHTML` insertion.
+
+Path C: oversized file to app memory exhaustion, now blocked for reviewed inline paths.
+
+1. User imports or drops an extremely large file.
+2. Renderer/backend allocate full file contents and base64 copies.
+3. App becomes slow or crashes.
+4. Defensive breakpoints now added: import and inline upload size caps.
+
+Path D: direct VNC over hostile network, still open by design.
+
+1. User disables SSH tunnel and connects to a VNC server over an untrusted network.
+2. Network attacker observes/tampers with VNC traffic if protocol security is weak.
+3. Defensive breakpoint: use SSH tunnel; future UI warning recommended.
+
+## 9. Denial-of-Service Review
+
+Fixed DoS controls:
+
+- Plain profile import now rejects payloads over 5 MiB.
+- Encrypted profile import now rejects files over 10 MiB before `os.ReadFile`.
+- Drag-drop SFTP upload now rejects files over 25 MiB in the frontend and backend before base64 decode.
+- Null profile entries no longer panic import paths.
+
+Checked and not found:
+
+- SQL queries use parameters for profile and audit operations reviewed.
+- GitHub repo fetch has timeouts and caps repository listing at 5000 repos.
+- SSH/Telnet/RAW connection setup uses dial timeouts.
+- VNC local proxy binds to loopback and uses a per-session token in the current code.
+
+Residual DoS risks:
+
+- RAW session history and terminal recordings can grow with long sessions.
+- SFTP directory listing still depends on remote server behavior and could return very large directories.
+- Direct VNC proxy bridges long-lived streams by design.
+
+## 10. Dependency and Supply-Chain Review
+
+Fixed:
+
+- `esbuild` upgraded to `^0.28.1`; `npm audit --json` now reports zero vulnerabilities.
+- `golang.org/x/net` upgraded to `v0.55.0`; govulncheck now reports no vulnerabilities.
+- Release workflow uses `npm ci` and pinned Wails CLI version.
+- `release.sh` uses `npm ci` when a lockfile exists and installs the Wails CLI at the version from `go.mod`.
+
+Checked:
+
+- `go.mod`, `go.sum`, `frontend/package.json`, `frontend/package-lock.json`.
+- `.github/workflows/release-builds.yml`, `build.sh`, `release.sh`.
+
+Notes:
+
+- npm warns that `xterm` packages are deprecated in favor of the newer `@xterm/*` packages. That is not an active vulnerability from `npm audit`, but it is a maintenance risk.
+
+## 11. Secrets and Sensitive Data Review
+
+Checked:
+
+- Repository search for private key markers, common cloud tokens, GitHub token prefixes, and obvious password assignments.
+- Secret store uses AES-GCM with Argon2id-derived keys and writes vault data with `0600`.
+- Profile export redacts inline SSH proxy/TOTP secrets when non-secret export mode is used.
+
+No high-confidence committed secrets or private keys were found.
+
+Residual notes:
+
+- GitHub and remote connection tokens are still available to the running app process by design.
+- Audit logging should continue to avoid logging raw secrets; reviewed audit messages do not include secret values.
+
+## 12. Authentication and Authorisation Review
+
+This is a desktop app, so there are no multi-user server authz roles in the reviewed code.
+
+Checked/fixed:
+
+- SSH host-key bypass helper removed by making `sshclient.Connect` fail closed.
+- Current SSH and VNC tunnel paths use explicit host-key callbacks.
+- GitHub API base URL validation now reduces token leakage to remote HTTP endpoints.
+
+Residual:
+
+- Users can still choose insecure protocols/modes such as direct VNC or legacy Telnet/RAW TCP.
+
+## 13. Input Validation and Output Encoding Review
+
+Fixed:
+
+- API create/update now validates profiles before persistence.
+- Plain and encrypted import validate every profile before storage.
+- GitHub API URLs now require HTTPS except loopback and reject URL credentials.
+- VNC validation supports VNC-specific host fallback and validates tunnel fields.
+- File-drop filename is escaped before template insertion.
+
+Checked:
+
+- SSH key management already rejects path traversal key names with alphanumeric, hyphen, and underscore constraints.
+- SFTP dropped filenames use `filepath.Base` before remote path construction.
+
+## 14. Frontend HTML/JavaScript Robustness Review
+
+Fixed:
+
+- File-drop modal filename sink now uses `escapeHtml`.
+- Drag-drop upload rejects files over 25 MiB before FileReader allocation.
+
+Checked:
+
+- Notifications render messages with `textContent`.
+- GitHub repository card fields reviewed use `textContent` or escaping for remote metadata.
+
+Not fully exercised:
+
+- No live Wails UI/browser automation was run in this audit. Add frontend interaction tests for file-drop, import/export, and update UI in future work.
+
+## 15. Infrastructure and Deployment Review
+
+Fixed:
+
+- GitHub Actions release workflow now uses pinned Wails CLI and `npm ci`.
+- Local `release.sh` now uses pinned Wails CLI and `npm ci`.
+
+Checked:
+
+- No Docker, Kubernetes, Terraform, or cloud deployment config was present in the reviewed file list.
+- Wails config was reviewed for frontend build/install commands.
+
+Residual:
+
+- Release artifacts are not signed/notarized in the reviewed workflow.
+- CI workflow has `contents: write`, required for release attachment, but should remain limited to release jobs.
+
+## 16. Logging, Monitoring, and Error Handling Review
+
+Checked:
+
+- Audit log records profile changes, import/export counts, connects/disconnects, and secret access without raw secret values.
+- Fixed import validation returns actionable errors rather than panics.
+- Frontend upload errors now surface a user-safe oversized-file message.
+
+Residual:
+
+- Some protocol errors are emitted directly to the UI. Continue avoiding credentials in error strings from remote services.
+- Consider adding structured debug logs for rejected imports without dumping payloads.
+
+## 17. Test Coverage and Security Regression Gaps
+
+Added/updated tests:
+
+- API rejects unsafe GitHub base URL.
+- API rejects null and oversized imports.
+- API rejects oversized inline SFTP upload before session lookup.
+- Export/import rejects oversized encrypted files.
+- Storage import rejects null profile entries and invalid strategy before looping.
+- Validation covers GitHub URL and VNC host/tunnel cases.
+- SSH client `Connect` requires explicit host-key callback.
+
+Remaining gaps:
+
+- Browser/Wails interaction tests for file-drop XSS and upload cap.
+- Load tests for very large SFTP directories, RAW history, and recordings.
+- End-to-end import/export tests through the actual Wails UI.
+- Release workflow provenance/signing tests.
+
+## 18. Prioritised Remediation Plan
+
+Immediate:
+
+- Keep the fixed tests in CI.
+- Add `npm audit` and govulncheck to CI if not already present.
+- Warn users when saving or connecting direct VNC profiles without SSH tunnelling.
+
+Short-term:
+
+- Replace deprecated `xterm` packages with maintained `@xterm/*` packages.
+- Add frontend tests for DOM injection via filenames and imported profile metadata.
+- Add streaming drag-drop upload support or route large drops through the native file upload path.
+
+Medium-term:
+
+- Add release artifact signing/notarization and checksums with provenance.
+- Add application-level limits for RAW history, terminal recording size, SFTP listing size, and GitHub error body reads.
+
+Long-term:
+
+- Add a security-focused CI job: tests, `npm audit`, govulncheck, secret scanning, and static DOM-sink checks.
+- Introduce a profile schema version and migration/normalization layer for imports.
+
+## 19. False Positives / Needs Manual Verification
+
+- `govulncheck -show verbose` initially reported module-level `x/net` advisories that were not reachable. The module was still upgraded to remove latent risk.
+- Direct VNC is intentionally supported; risk depends on network trust and VNC server security type.
+- File-drop XSS was fixed by code inspection; manual Wails UI verification should still be added.
+- No live external service testing was performed.
+
+## 20. Final Notes
+
+The repo is in a materially better state after this run: profile data is validated before storage, local resource-consumption paths are bounded, the file-drop DOM sink is escaped, dependency scanners are clean, and release dependency installation is more reproducible.
+
+The main residual security posture issue is user-selected insecure connectivity: Telnet/RAW/direct VNC remain useful but should be presented with clear safety context.

audits/20260616-1111-functionalityNextSteps.md

@@ -0,0 +1,81 @@
+# Functionality and Next Steps Report
+
+## 1. Executive Summary
+
+This fix pass moves Nexus closer to predictable large-file behavior: file-backed Leviathan documents stay file-backed for save/export, recordings parse incrementally, and unavoidable in-memory parsers now advertise and enforce clear limits.
+
+The most useful next work is to surface these limits in the Leviathan UI and add user-facing guidance when an operation needs a smaller selection or a streaming implementation.
+
+## 2. Current Functional Risks
+
+Leviathan spectrogram conversion still uses bounded in-memory audio/image buffers because the current encoder/decoder APIs operate on byte slices. Very large images, MP3s, WAVs, or decoded MP3 output will now be rejected with an error rather than processed.
+
+PDF, certificate, and key scanners still operate on bounded whole-document buffers for structural parsing. The cap avoids memory denial of service, but users working with very large firmware or document corpora may need range-based scans in future.
+
+Recording playback is now line-streamed, but the returned API shape still collects parsed events before sending them to the frontend. Very long recordings are still protected by the playback cap; true progressive playback would require an API contract change.
+
+## 3. Code Quality Improvements Completed
+
+Chunk-first behavior:
+
+- Leviathan working-copy save now writes with `Document.ForEachChunk`.
+- Leviathan case export now streams `working.bin` into the zip file on disk.
+- Recording playback parses line-by-line instead of reading and splitting the whole file.
+
+Bounded read behavior:
+
+- Spectrogram image/audio inputs reject oversize data before decode.
+- Image decode checks dimensions before allocating decoded pixels.
+- HTTP response helpers cap JSON and error bodies.
+- SSH key, VNC key, vault, public-key, PDF, and BinSnoop file reads have explicit limits.
+
+Responsiveness:
+
+- Heavy Leviathan spectrogram/export operations no longer hold the engine lock while processing or showing native save dialogs.
+
+## 4. Frontend Interaction and Error Handling
+
+Recommended UI follow-up:
+
+- Show limit-aware messages for spectrogram tools, such as image max size, audio max size, and decoded image dimension limits.
+- For PDF/cert/key tools, show “scan a smaller file or selected range” guidance when caps are hit.
+- Add a small status line in Leviathan for whether an operation is streaming, bounded-buffer, or selection-based.
+- For recording playback, consider progressive playback loading so long recordings do not need all parsed events returned at once.
+
+## 5. Testing Roadmap
+
+Completed in this pass:
+
+- Oversized spectrogram image dimensions are rejected before full decode.
+- Leviathan bounded document reads reject oversize documents.
+- Patched working-file writes preserve changed bytes.
+- Oversized GitHub/update responses are rejected.
+- Oversized SSH public keys, vault files, PDFs, and BinSnoop files are rejected.
+
+Recommended next tests:
+
+- Wails UI tests for Leviathan oversized image/audio/PDF error messages.
+- A case-export test that opens a sparse file-backed document and verifies the zip is produced without materializing `working.bin`.
+- A recording playback test with malformed lines and a long valid event stream.
+- Browser interaction tests for the Leviathan tab while a long analysis is running.
+
+## 6. Recommended New Functionality
+
+Add range-based versions of whole-document Leviathan tools:
+
+- `keys.scanRange`
+- `certs.scanRange`
+- `pdf.quickScan` for headers/xref/trailer without full structural recovery
+- `spectrogram.renderRange` for selected audio windows
+
+Add streaming media support later:
+
+- Decode audio from file/range readers instead of complete byte slices.
+- Stream WAV output directly to disk for spectrogram generation.
+- Stream image insertion output to disk when carrier audio is large.
+
+## 7. Caveats
+
+The new caps trade permissiveness for stability. Files above the limits now fail fast instead of attempting best-effort processing.
+
+The frontend build and regression checks passed, but I did not run a packaged Wails app manually in this pass.

audits/20260616-1111-securityAudit.md

@@ -0,0 +1,135 @@
+# Security Audit Report
+
+## 1. Executive Summary
+
+This fix-mode audit focused on file-reading and response-reading paths that could allocate complete files or unbounded remote bodies in memory.
+
+The main risk fixed was local denial of service from large user-selected files, imported Leviathan artefacts, recordings, SSH key files, vault files, and remote update/GitHub API responses. Where the codebase already had a chunked document model, saves and exports now use it. Where a parser still requires a complete byte slice, the code now rejects oversized inputs before allocation.
+
+Verification passed with targeted package tests, `go test ./...`, frontend regression tests, frontend build, and `git diff --check`.
+
+## 2. Scope Reviewed
+
+Reviewed and changed:
+
+- Leviathan file-backed document save, case export, spectrogram image/audio conversion, PDF parsing, and BinSnoop file helpers.
+- Wails API helpers that read SSH public keys and Leviathan image/audio inputs.
+- SSH and VNC tunnel private-key loading.
+- GitHub client and update-checker HTTP response handling.
+- Recording playback parsing.
+- Encrypted secrets vault loading.
+
+Not live-tested:
+
+- A packaged Wails desktop binary.
+- Real remote SSH/VNC/GitHub endpoints.
+- Very large real-world media corpora beyond automated guard tests.
+
+## 3. Methodology
+
+I searched for `ReadFile`, `ReadAll`, and whole-document `Range(0, size)` patterns, then classified each as chunked, bounded, embedded/test-only, or unsafe. Fixes were kept to low-risk local changes:
+
+- Prefer `Document.ForEachChunk` for writing/exporting working file bytes.
+- Stream line-oriented recordings with `bufio.Scanner`.
+- Limit HTTP response reads with `io.LimitReader`.
+- Add `os.Stat` size checks before unavoidable bounded `os.ReadFile` calls.
+- Add parser-specific caps before whole-document reads.
+
+## 4. Findings Summary
+
+| ID | Severity | Confidence | Title | Component | Status |
+|---|---:|---:|---|---|---|
+| SEC-20260616-001 | Medium | High | Leviathan save/export and spectrogram tools could materialize large files | Leviathan API, spectrogram | Fixed |
+| SEC-20260616-002 | Medium | High | Remote API/update responses were read without size limits | GitHub client, updater | Fixed |
+| SEC-20260616-003 | Medium | High | Local app data/key reads lacked size caps | SSH keys, VNC keys, vault, BinSnoop | Fixed |
+| SEC-20260616-004 | Low | High | Recording playback loaded the whole capped recording file | Recording playback | Fixed |
+| SEC-20260616-005 | Low | Medium | Some parsers still require complete bounded buffers | PDF, cert/key scanners, media decoders | Accepted with caps |
+
+## 5. Detailed Findings
+
+### SEC-20260616-001: Leviathan full-file allocation paths
+
+Leviathan save/export and spectrogram operations could duplicate entire working files in memory. Case export also built the zip archive in memory before writing it.
+
+Fixed in:
+
+- `internal/api/leviathan.go`
+- `internal/leviathan/spectrogram/spectrogram.go`
+- `internal/leviathan/pdf/pdf.go`
+
+Changes:
+
+- Working-copy save writes via `Document.ForEachChunk`.
+- Case export streams `working.bin` directly into `zip.Writer` backed by the destination file.
+- Spectrogram encode/view/insert rejects oversized image/audio documents before bounded decode.
+- Image decoding checks compressed byte size and decoded pixel dimensions before full image decode.
+- PDF parsing rejects files above 128 MiB before whole-document structural parsing.
+- Long-running spectrogram/export tools no longer hold the Leviathan engine lock while doing heavy work or native save dialogs.
+
+### SEC-20260616-002: Unbounded remote response reads
+
+GitHub and update-check response bodies could be read without an explicit maximum.
+
+Fixed in:
+
+- `internal/githubclient/githubclient.go`
+- `internal/updater/updater.go`
+
+Changes:
+
+- GitHub JSON responses are capped at 4 MiB.
+- GitHub error bodies are capped at 64 KiB.
+- Update release/manifest responses are capped at 1 MiB.
+- Repository archive downloads continue to stream to disk instead of memory.
+
+### SEC-20260616-003: Local key/vault/helper reads lacked caps
+
+Several local helper paths read files directly even though the expected files are small.
+
+Fixed in:
+
+- `internal/api/api.go`
+- `internal/sshclient/sshclient.go`
+- `internal/sessions/manager.go`
+- `internal/secrets/secrets.go`
+- `internal/leviathan/binsnoop/common.go`
+- `internal/leviathan/binsnoop/binsnoop.go`
+
+Changes:
+
+- SSH public keys are capped at 64 KiB.
+- SSH private keys for SSH and VNC tunnel auth are capped at 1 MiB.
+- Secret vault files are capped at 10 MiB.
+- BinSnoop direct file helpers are capped at 64 MiB; the UI path already uses a bounded buffer.
+
+### SEC-20260616-004: Recording playback whole-file read
+
+Recording playback had a 100 MiB file cap, but still read and split the full file in memory.
+
+Fixed in:
+
+- `internal/recording/recorder.go`
+
+Changes:
+
+- Playback now opens the recording and scans line-by-line.
+- Individual playback lines are capped at 8 MiB.
+- Existing malformed-event tolerance is preserved.
+
+## 6. Residual Risk
+
+Some operations still need bounded complete buffers because downstream parsers or decoders require byte slices: image/audio spectrogram conversion, PDF structural parsing, certificate/key scanning, and small SSH/vault/public-key parsing. These now fail before allocation when inputs exceed explicit caps.
+
+Truly streaming versions of every binary parser would be a larger Leviathan architecture project. The current fixes remove the unbounded allocation behavior while preserving tool behavior for normal files.
+
+## 7. Verification
+
+Passed:
+
+- `go test ./internal/api ./internal/leviathan/spectrogram ./internal/leviathan/pdf ./internal/leviathan/binsnoop ./internal/updater ./internal/githubclient ./internal/secrets ./internal/recording ./internal/sshclient ./internal/sessions -count=1`
+- `go test ./... -count=1`
+- `npm --prefix frontend test`
+- `npm --prefix frontend run build`
+- `git diff --check`
+
+New tests cover oversized GitHub/update bodies, oversized spectrogram images, bounded Leviathan document reads, chunked patched-file writes, oversized public keys, oversized vault files, oversized PDFs, and BinSnoop file caps.

audits/20260616-1702-functionalityNextSteps.md

@@ -0,0 +1,138 @@
+# Functionality and Next Steps Report
+
+## 1. Executive Summary
+
+This fix pass improved robustness around local proxying, file imports, remote downloads, SSH key management, and frontend rendering. The app now fails earlier and more predictably when inputs are malformed or too large.
+
+Highest-impact next steps:
+
+- Manually verify packaged VNC connections after the new Origin allowlist.
+- Add UI copy for newly enforced limits.
+- Add CI coverage for the security checks run in this pass.
+- Continue frontend cleanup around dynamic `innerHTML`.
+
+## 2. Current Functional Risks
+
+VNC runtime compatibility:
+
+- The backend now allows missing, `wails://`, and loopback HTTP(S) origins. This should work for Wails/noVNC, but packaged app validation is still needed.
+
+Large-file and large-download behavior:
+
+- GitHub archive downloads now stop at 2 GiB. Very large repositories will fail fast.
+- SSH config imports now reject files above 5 MiB or more than 5000 Host blocks.
+
+SSH key generation:
+
+- RSA key generation is limited to 2048, 3072, and 4096 bits and times out after 30 seconds.
+- Slow systems should be checked with RSA 4096 to ensure the timeout is not too tight.
+
+Frontend:
+
+- SSH key manager dynamic rendering is safer. Other static `innerHTML` templates remain and should be reviewed when they take dynamic data.
+
+## 3. Code Quality Improvements
+
+Completed:
+
+- Added focused helper functions for VNC Origin validation.
+- Centralized GitHub endpoint construction and owner/repo parsing.
+- Added reusable archive stream limiting.
+- Added backend SSH key generation option validation.
+- Added import bounds to the SSH config parser.
+- Replaced SSH key manager dynamic modal HTML with DOM construction.
+
+Recommended refactors:
+
+- Move file-size and stream-size caps into named settings or a shared limits package if more subsystems need them.
+- Add a small frontend helper for safe modal construction so feature code stops hand-rolling modal `innerHTML`.
+- Consider a common backend "safe basename" helper for local and remote file operations.
+
+## 4. Frontend Interaction and Error-Handling Improvements
+
+Recommended:
+
+- Show a specific VNC connection error if the proxy rejects an unexpected Origin in packaged builds.
+- Show clear messages for SSH config files that exceed size or Host-block limits.
+- Show clear messages for GitHub archives above the cap.
+- Add a hostile-filename E2E test for the SSH key delete confirmation modal.
+- Continue converting dynamic modal content to DOM nodes or `textContent`.
+
+## 5. Testing Roadmap
+
+Added in this pass:
+
+- VNC Origin allowlist tests.
+- SFTP upload parent-directory rejection tests.
+- SSH config file and Host-block limit tests.
+- SSH key generation option validation tests.
+- GitHub path escaping and archive cap tests.
+- Frontend regression checks for SSH key manager text rendering.
+
+Next tests:
+
+- Packaged Wails VNC smoke test on macOS, Windows, and Linux.
+- Browser/E2E test for SSH key filenames containing `<`, `>`, quotes, and ampersands.
+- HTTP integration test for GitHub archive download caps and escaped branch refs.
+- UI tests for limit-aware error messages.
+- CI job that runs Go tests, frontend tests, frontend build, `npm audit --omit=dev`, `govulncheck`, and `git diff --check`.
+
+## 6. Recommended New Functionality
+
+Useful additions:
+
+- Preferences for maximum GitHub archive download size.
+- A pre-download confirmation for large GitHub archives when Content-Length is known.
+- Import preview for OpenSSH config showing Host count before persistence.
+- A diagnostics panel for VNC proxy status, including local URL redaction, Origin decisions, and connection state.
+- A unified "Limits" help page that lists SFTP upload caps, GitHub archive cap, SSH config import cap, and Leviathan file caps.
+
+## 7. Next-Level Opportunities
+
+Architecture:
+
+- Centralize resource limits and expose them to both Go and frontend UI copy.
+- Add a secure modal builder and migrate risky frontend dialogs gradually.
+- Add structured security regression tests for every Wails method that accepts file paths, filenames, URLs, or base64 payloads.
+
+Operations:
+
+- Generate checksums for release artifacts.
+- Generate an SBOM during release.
+- Publish a short security hardening checklist in `docs/build-and-release.md`.
+
+Developer experience:
+
+- Add a `make security-check` target that runs the same commands used in this audit.
+- Add pre-commit or CI checks for `gofmt`, `go test`, frontend regression tests, and `git diff --check`.
+
+## 8. Prioritised Action Plan
+
+Immediate:
+
+- Manually test packaged VNC on all supported platforms.
+- Keep the security patch tests in CI before release.
+
+Short-term:
+
+- Add user-facing messages for the new SSH config, GitHub archive, and SSH keygen limits.
+- Add E2E coverage for hostile SSH key filenames.
+- Add an HTTP test around GitHub archive download behavior.
+
+Medium-term:
+
+- Centralize app resource limits and expose them to UI/help.
+- Migrate high-risk frontend dynamic HTML patterns to safe modal helpers.
+- Add release checksums and SBOM generation.
+
+Long-term:
+
+- Add progressive/streaming UX for large GitHub and SFTP transfers.
+- Build a cross-platform packaged-app smoke test suite for Wails integrations.
+
+## 9. Caveats and Validation Needed
+
+- VNC Origin compatibility must be validated in packaged builds, not only unit tests.
+- The 2 GiB GitHub archive cap may need product tuning for users with very large repositories.
+- RSA 4096 key generation timeout should be checked on lower-powered machines.
+- The frontend build passed, but this pass did not interactively click through the SSH key modal in a real browser/WebView.

audits/20260616-1702-securityAudit.md

@@ -0,0 +1,641 @@
+# Security Audit Report
+
+## 1. Executive Summary
+
+This fix-mode audit reviewed the Wails API surface, local proxy behavior, file import paths, SSH key management, GitHub integration, frontend DOM sinks, dependency manifests, tests, and release workflow.
+
+Six concrete issues were fixed:
+
+- The local VNC WebSocket proxy accepted any browser `Origin` and did not cap client-to-proxy WebSocket message size.
+- SFTP browser uploads accepted the special filename `..`, allowing a Wails caller to escape the selected remote directory when the name was joined.
+- SSH config import parsed line-by-line but had no total file or Host-block cap.
+- Backend SSH key generation trusted caller-supplied key type and RSA bit count and had no process timeout.
+- GitHub repo/ref values were interpolated into API paths without escaping, and archive downloads had no explicit stream cap.
+- SSH key manager UI interpolated backend errors and filesystem-derived key names into `innerHTML`.
+
+Verification passed with targeted Go tests, full Go tests, frontend regression checks, frontend build, `npm audit --omit=dev`, `govulncheck`, and `git diff --check`.
+
+## 2. Scope Reviewed
+
+Reviewed:
+
+- Go backend packages under `internal/`: API bindings, VNC proxy, GitHub client, SSH config import, SSH key management, SFTP upload helpers, validation, sessions, storage, secrets, updater, recording, Leviathan parser bounds, and tests.
+- Browser-facing JavaScript under `frontend/src/js`, especially SSH key management, SFTP upload flows, VNC integration, and dynamic HTML usage.
+- Frontend package manifest, lockfile, build scripts, and regression script.
+- Go module dependencies and reachable vulnerability state.
+- GitHub Actions release workflow.
+
+Not fully live-tested:
+
+- A packaged Wails desktop binary.
+- Real noVNC connections inside the packaged WebView after the new Origin policy.
+- Real GitHub Enterprise archive downloads above normal repository sizes.
+
+## 3. Methodology
+
+The review used static analysis, targeted source searches, dependency/advisory tooling, and focused regression tests. I mapped attacker-controlled inputs from the renderer and local files into Go methods, network clients, local HTTP/WebSocket services, subprocesses, remote SFTP paths, and DOM sinks. I prioritized issues that could be fixed with small behavior-preserving changes and backed by tests.
+
+Commands run:
+
+- `go test ./internal/vncclient ./internal/api ./internal/sshconfig ./internal/githubclient -count=1`
+- `npm --prefix frontend test`
+- `git diff --check`
+- `go test ./... -count=1`
+- `npm --prefix frontend run build`
+- `npm --prefix frontend audit --omit=dev`
+- `go run golang.org/x/vuln/cmd/govulncheck@latest ./...`
+
+## 4. Risk Rating Method
+
+Severity reflects exploit prerequisite, affected trust boundary, likely impact, and availability/confidentiality/integrity outcome:
+
+- Critical: remote unauthenticated compromise or secret disclosure.
+- High: practical compromise of credentials, host access, or arbitrary code execution.
+- Medium: meaningful local, renderer, remote service, or connected-server abuse with realistic prerequisites.
+- Low: local robustness issues, bounded DoS, or defense-in-depth gaps.
+- Informational: observations and hardening opportunities.
+
+Confidence reflects direct code evidence and testability. Findings fixed here are High confidence because they map to concrete files and new regression tests.
+
+## 5. Attack Surface Map
+
+Entry points:
+
+- Wails-bound `api.Service` methods callable from the renderer.
+- Local VNC WebSocket proxy bound to `127.0.0.1` on a random port and random token path.
+- SSH, Telnet, RAW TCP, VNC, SFTP, GitHub, updater, and Leviathan binary-analysis workflows.
+- Profile import/export, encrypted `.nexus` import, OpenSSH config import, recording playback, SSH key generation/deletion, and drag/drop upload flows.
+
+Trust boundaries:
+
+- Renderer to Go backend.
+- Local browser/WebView to loopback VNC proxy.
+- Local filesystem files selected or scanned by the app.
+- Remote SSH/SFTP/VNC/GitHub/update endpoints.
+- OS keychain/encrypted vault to profile storage and session runtime.
+
+Attacker starting positions considered:
+
+- Malicious local webpage attempting loopback WebSocket access.
+- Malicious or compromised renderer script.
+- Malicious local filename or selected config/import file.
+- Malicious GitHub Enterprise/API endpoint or unusual repo/ref metadata.
+- Malicious connected SSH/SFTP/VNC host.
+
+## 6. Findings Summary Table
+
+| ID | Severity | Confidence | Title | Component | Status |
+|---|---|---|---|---|---|
+| SEC-20260616-1702-001 | Medium | High | VNC proxy allowed all origins and uncapped WebSocket frames | `internal/vncclient` | Fixed |
+| SEC-20260616-1702-002 | Medium | High | SFTP upload name `..` escaped selected remote directory | `internal/api` SFTP upload helpers | Fixed |
+| SEC-20260616-1702-003 | Low | High | SSH config import lacked total file and Host-block bounds | `internal/sshconfig` | Fixed |
+| SEC-20260616-1702-004 | Low | High | SSH key generation allowed expensive caller-controlled options without timeout | `internal/api` SSH key management | Fixed |
+| SEC-20260616-1702-005 | Medium | High | GitHub repo/ref path interpolation and uncapped archive stream | `internal/githubclient` | Fixed |
+| SEC-20260616-1702-006 | Medium | High | SSH key manager rendered key names/errors through dynamic `innerHTML` | `frontend/src/js/sshkeys.js` | Fixed |
+
+## 7. Detailed Findings
+
+### Finding ID: SEC-20260616-1702-001
+
+#### Title
+
+VNC proxy allowed all origins and uncapped WebSocket frames
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/vncclient/vncclient.go`
+- `internal/vncclient/vncclient_test.go`
+- Local noVNC WebSocket proxy
+
+#### Description
+
+The VNC proxy was bound to loopback and protected by a random token path, but its Gorilla WebSocket upgrader accepted every `Origin`. It also read WebSocket messages without an explicit message size limit. If a proxy URL token leaked through logs, UI state, injected renderer code, or another local channel, a non-local browser origin could attempt to drive the active VNC TCP connection or send oversized frames that force memory allocation.
+
+#### Evidence
+
+Before the fix, `websocket.Upgrader.CheckOrigin` returned `true` for every request, and the proxy called `ws.ReadMessage()` without `SetReadLimit`.
+
+#### Attack Scenario
+
+A malicious local webpage or injected renderer script obtains an active `ws://127.0.0.1:<port>/<token>` URL. Because all origins were accepted, it could connect from a non-app origin and send very large WebSocket messages or VNC protocol bytes into the bridged TCP connection.
+
+#### Impact
+
+Potential local cross-origin abuse of active VNC sessions if the token is exposed, and avoidable memory pressure from oversized client-to-proxy WebSocket frames.
+
+#### Recommendation
+
+Allow only Wails and loopback browser origins, keep accepting missing origins for non-browser clients, and cap inbound WebSocket message size.
+
+#### Safer Example
+
+Implemented `allowProxyOrigin`, `isLoopbackHost`, and `ws.SetReadLimit(maxWebSocketMessageBytes)`.
+
+#### Suggested Tests
+
+Added `TestAllowProxyOrigin` for missing, Wails, loopback, remote, lookalike, and malformed origins.
+
+#### References
+
+- CWE-346: Origin Validation Error
+- CWE-400: Uncontrolled Resource Consumption
+- OWASP ASVS 14.4: HTTP security configuration
+
+#### Assumptions / Limitations
+
+The packaged Wails WebView should be manually tested to confirm its runtime Origin is covered by the `wails://` allow rule.
+
+### Finding ID: SEC-20260616-1702-002
+
+#### Title
+
+SFTP upload name `..` escaped selected remote directory
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/api/api.go`
+- `internal/api/api_test.go`
+- `SFTPUploadData`
+- `SFTPUploadStart`
+
+#### Description
+
+`safeSFTPUploadName` normalized slash variants and used `path.Base`, but did not reject the special basename `..`. `path.Join(remoteDir, "..")` resolves to the parent directory, so a Wails caller could escape the selected upload directory.
+
+#### Evidence
+
+The previous rejection covered empty, `.`, `/`, and NUL, but not `..`. The upload methods then used `path.Join(remoteDir, safeName)`.
+
+#### Attack Scenario
+
+A malicious renderer call invokes chunked upload with `remoteDir="/home/user/upload"` and `fileName=".."`. The destination path resolves to `/home/user`, outside the selected directory.
+
+#### Impact
+
+Unexpected remote writes/truncation attempts outside the user's selected SFTP directory, depending on server permissions and target type.
+
+#### Recommendation
+
+Reject `..` after basename normalization.
+
+#### Safer Example
+
+Implemented `safeName == ".."` rejection.
+
+#### Suggested Tests
+
+Added `TestSafeSFTPUploadNameRejectsParentDirectory`.
+
+#### References
+
+- CWE-22: Path Traversal
+- OWASP ASVS 12.3: File path control
+
+#### Assumptions / Limitations
+
+The browser `File.name` API normally does not produce `..`, but Wails API methods are still a trust boundary and should validate independently.
+
+### Finding ID: SEC-20260616-1702-003
+
+#### Title
+
+SSH config import lacked total file and Host-block bounds
+
+#### Severity
+
+Low
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/sshconfig/sshconfig.go`
+- `internal/sshconfig/sshconfig_test.go`
+- `ImportSSHConfig`
+
+#### Description
+
+The OpenSSH config parser scanned files line-by-line, but it did not cap total file size or the number of accumulated Host blocks. A very large selected config could allocate a large slice of parsed blocks and profiles.
+
+#### Evidence
+
+`ParseFile` opened the file and appended Host blocks to an in-memory slice until EOF.
+
+#### Attack Scenario
+
+A user imports a hostile or accidentally huge SSH config containing thousands of Host blocks. The app spends unnecessary CPU and memory parsing and converting entries.
+
+#### Impact
+
+Local denial of service or UI unresponsiveness during import.
+
+#### Recommendation
+
+Reject oversized config files, set a scanner line cap, and reject excessive Host-block counts.
+
+#### Safer Example
+
+Implemented `maxConfigFileBytes`, `maxConfigLineBytes`, and `maxHostBlocks`.
+
+#### Suggested Tests
+
+Added oversized-file and excessive-Host-block tests.
+
+#### References
+
+- CWE-400: Uncontrolled Resource Consumption
+
+#### Assumptions / Limitations
+
+The selected caps are conservative for normal OpenSSH config files. Extremely large enterprise configs may need batch import support later.
+
+### Finding ID: SEC-20260616-1702-004
+
+#### Title
+
+SSH key generation allowed expensive caller-controlled options without timeout
+
+#### Severity
+
+Low
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/api/api.go`
+- `internal/api/api_test.go`
+- `GenerateSSHKey`
+
+#### Description
+
+The frontend exposes fixed key-type and bit-size choices, but the backend method accepted caller-supplied values directly and ran `ssh-keygen` without a context timeout. A malformed renderer call could request unsupported types or excessive RSA bit sizes, tying up the subprocess.
+
+#### Evidence
+
+`GenerateSSHKey` passed `keyType` to `ssh-keygen -t` and only checked `bits > 0` for RSA before adding `-b`.
+
+#### Attack Scenario
+
+A malicious renderer call requests a very large RSA key size. `ssh-keygen` consumes CPU for an extended period or fails slowly.
+
+#### Impact
+
+Local CPU denial of service and poor recovery if the subprocess hangs.
+
+#### Recommendation
+
+Validate allowed key types and RSA sizes server-side, and execute `ssh-keygen` with a timeout.
+
+#### Safer Example
+
+Implemented `validateSSHKeyGenerationOptions` and `exec.CommandContext` with a 30 second timeout.
+
+#### Suggested Tests
+
+Added validation tests for defaults, RSA defaults, oversized RSA sizes, and unsupported key types.
+
+#### References
+
+- CWE-400: Uncontrolled Resource Consumption
+- CWE-20: Improper Input Validation
+
+#### Assumptions / Limitations
+
+The timeout is a safety net, not a substitute for platform-level process controls. Real key generation should still be manually tested on slower hardware.
+
+### Finding ID: SEC-20260616-1702-005
+
+#### Title
+
+GitHub repo/ref path interpolation and uncapped archive stream
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/githubclient/githubclient.go`
+- `internal/githubclient/githubclient_test.go`
+- `FetchLatestCommit`
+- `DownloadRepoArchive`
+
+#### Description
+
+Repository full names and refs were interpolated into REST API paths without escaping. The archive download also streamed response bodies to disk without an explicit maximum. A malformed renderer call, unusual branch name, or compromised GitHub Enterprise endpoint could create surprising request paths or consume disk.
+
+#### Evidence
+
+The client built paths with `fmt.Sprintf("%s/repos/%s/commits/%s", ...)` and copied archives with `io.Copy(file, resp.Body)`.
+
+#### Attack Scenario
+
+A renderer calls archive download with a malformed repo full name containing extra path segments, or a malicious GitHub Enterprise endpoint returns an unbounded archive response.
+
+#### Impact
+
+Potential confused API requests using the user's GitHub token and local disk exhaustion from unbounded archive streams.
+
+#### Recommendation
+
+Require `owner/repo` format, URL-escape each API path segment, and cap archive streams.
+
+#### Safer Example
+
+Implemented `splitRepoFullName`, `endpointURL`, `copyLimitedArchive`, and a 2 GiB archive cap.
+
+#### Suggested Tests
+
+Added tests for escaped refs, malformed repo names, archive limit rejection, and at-limit copies.
+
+#### References
+
+- CWE-20: Improper Input Validation
+- CWE-22: Path Traversal style path confusion
+- CWE-400: Uncontrolled Resource Consumption
+
+#### Assumptions / Limitations
+
+The 2 GiB archive cap may reject unusually large repositories. A future preferences setting could make this user-configurable.
+
+### Finding ID: SEC-20260616-1702-006
+
+#### Title
+
+SSH key manager rendered key names/errors through dynamic `innerHTML`
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `frontend/src/js/sshkeys.js`
+- `frontend/scripts/test-regressions.js`
+- SSH key manager modal
+
+#### Description
+
+The SSH key manager interpolated backend error text and confirmation title/message/button text into `innerHTML`. Key names are derived from local `~/.ssh/*.pub` filenames, so a malicious local filename could inject HTML into the delete confirmation modal.
+
+#### Evidence
+
+The previous code used `list.innerHTML = `<div ...>${err}</div>`` and built confirmation modal HTML with `${title}`, `${message}`, and `${confirmLabel}`.
+
+#### Attack Scenario
+
+A local attacker creates an SSH public key file with an HTML-like filename. When the user opens the key manager and deletes it, the filename is interpolated into modal HTML.
+
+#### Impact
+
+DOM XSS in the Wails renderer, with possible access to app UI actions exposed to the renderer.
+
+#### Recommendation
+
+Render dynamic strings with `textContent` or DOM node construction.
+
+#### Safer Example
+
+Implemented text-node rendering for key load errors and confirmation modal dynamic text.
+
+#### Suggested Tests
+
+Added frontend regression checks to prevent the vulnerable interpolation pattern from returning.
+
+#### References
+
+- CWE-79: Cross-Site Scripting
+- OWASP ASVS 5.3: Output encoding
+
+#### Assumptions / Limitations
+
+Other static-template `innerHTML` use remains in the frontend and should continue to be reviewed when it accepts dynamic values.
+
+## 8. Blackhat-Style Abuse Paths
+
+Path 1: Token leak to VNC abuse
+
+- Prerequisite: an active VNC proxy URL leaks to a non-app webpage or injected script.
+- Old path: any Origin could connect and send arbitrary WebSocket frames to the VNC TCP bridge.
+- Breakpoint added: Wails/loopback Origin allowlist plus message cap.
+
+Path 2: Renderer-to-remote path escape
+
+- Prerequisite: malicious renderer code or direct Wails call.
+- Old path: call SFTP upload with filename `..`, causing `path.Join(remoteDir, "..")`.
+- Breakpoint added: `..` is rejected after basename normalization.
+
+Path 3: Local filename to renderer script injection
+
+- Prerequisite: crafted key filename in `~/.ssh`.
+- Old path: key name appears in confirmation modal HTML.
+- Breakpoint added: key names and errors use `textContent`.
+
+Path 4: Malicious GitHub Enterprise response to disk pressure
+
+- Prerequisite: user connects to compromised or malicious API base URL allowed by profile validation.
+- Old path: archive stream was copied until EOF.
+- Breakpoint added: Content-Length precheck and streaming cap.
+
+## 9. Denial-of-Service Review
+
+Fixed resource-control issues:
+
+- VNC inbound WebSocket message cap.
+- SSH config file size, line size, and Host-block caps.
+- SSH key generation input validation and subprocess timeout.
+- GitHub archive stream cap.
+
+Previously fixed and rechecked from recent audit context:
+
+- GitHub/update JSON response caps.
+- Leviathan bounded reads and chunked save/export paths.
+- SFTP inline/chunk upload caps.
+- Secret vault and SSH key file read caps.
+
+Residual DoS considerations:
+
+- SFTP directory listings depend on remote server behavior and can still return large lists.
+- GitHub repository enrichment intentionally caps total repositories but still performs concurrent commit lookups.
+- Very large legitimate GitHub archives above 2 GiB now fail fast.
+
+## 10. Dependency and Supply-Chain Review
+
+Results:
+
+- `npm --prefix frontend audit --omit=dev`: 0 vulnerabilities.
+- `govulncheck ./...`: no vulnerabilities found.
+
+Reviewed manifests:
+
+- `go.mod`
+- `go.sum`
+- `frontend/package.json`
+- `frontend/package-lock.json`
+- `.github/workflows/release-builds.yml`
+
+No high-confidence dependency findings were found in this pass.
+
+## 11. Secrets and Sensitive Data Review
+
+Checked:
+
+- No obvious private keys, GitHub tokens, cloud keys, or hardcoded credentials were found in source outside documentation/examples.
+- Non-secret profile export redaction was already covered by tests.
+- Secret access logging records secret type, not value.
+- GitHub Authorization headers are set only in HTTP requests and not logged by this code.
+
+Residual:
+
+- Plain exports without secrets are safer, but encrypted export remains the recommended path for portable backups.
+- Local audit logs should continue to avoid host/user secrets in future features.
+
+## 12. Authentication and Authorisation Review
+
+This is a local desktop application, so there are no server-side user roles or tenant boundaries. Relevant controls reviewed:
+
+- SSH host-key callback requirement for VNC SSH tunnels.
+- Known-host storage and verification paths.
+- Secret retrieval via keychain/vault and prompt callbacks.
+- GitHub token validation before repo fetch.
+
+No missing multi-user authorization checks apply to the current architecture.
+
+## 13. Input Validation and Output Encoding Review
+
+Fixed:
+
+- SFTP upload basename `..`.
+- SSH key generation key type and RSA bit sizes.
+- GitHub repo full-name format and path segment escaping.
+- SSH key manager dynamic output encoding.
+
+Previously present controls:
+
+- Profile validation rejects invalid hosts, ports, secret modes, GitHub HTTP non-loopback base URLs, and malformed protocol configs.
+- Import profiles are size-capped and validated before persistence.
+
+## 14. Frontend HTML/JavaScript Robustness Review
+
+Fixed:
+
+- SSH key manager load errors now render via `textContent`.
+- SSH key deletion confirmation modal dynamic strings now render via DOM nodes/text.
+- Regression script now checks these patterns.
+
+Checked:
+
+- Wails service bridge ordering remains covered by regression checks.
+- SFTP drag/drop upload still uses chunked methods.
+- Direct VNC warning flow remains covered by regression checks.
+
+Residual:
+
+- Frontend still contains many static `innerHTML` templates. Future reviews should focus on any template that accepts local filesystem, remote host, profile, update, or GitHub data.
+
+## 15. Infrastructure and Deployment Review
+
+Reviewed:
+
+- GitHub Actions release workflow.
+- Wails build config.
+- Frontend build scripts.
+
+No new high-confidence release workflow finding was fixed. The workflow uses pinned major versions for common actions and default GitHub token permissions scoped to release attachment needs.
+
+Residual:
+
+- Consider adding checksums/SBOM generation for release artifacts.
+- Consider a CI job for `go test ./...`, frontend regression tests, `npm audit --omit=dev`, and `govulncheck`.
+
+## 16. Logging, Monitoring, and Error Handling Review
+
+Fixed:
+
+- SSH key manager no longer injects raw error strings into HTML.
+- GitHub malformed repo names now fail before request construction.
+- SSH keygen timeout returns a specific timeout error.
+
+Checked:
+
+- Error messages added in this pass do not include tokens, passwords, or key material.
+- Existing audit logger records profile/session actions and secret access metadata.
+
+## 17. Test Coverage and Security Regression Gaps
+
+Added:
+
+- VNC Origin allowlist tests.
+- SFTP parent-directory upload name tests.
+- SSH key generation option validation tests.
+- SSH config oversized file and Host-block cap tests.
+- GitHub URL escaping, malformed full-name, and archive cap tests.
+- Frontend static regression checks for SSH key manager safe rendering.
+
+Remaining gaps:
+
+- No packaged Wails/noVNC integration test for Origin behavior.
+- No E2E browser test for SSH key modal rendering with hostile filenames.
+- No integration test for GitHub archive cap against an HTTP test server.
+
+## 18. Prioritised Remediation Plan
+
+Immediate:
+
+- Manually test VNC connections in a packaged Wails app to verify the Origin allowlist.
+- Keep the new security tests in CI.
+
+Short-term:
+
+- Add an E2E test for SSH key manager hostile filenames.
+- Add an HTTP integration test for GitHub archive caps and escaped refs.
+- Surface user-friendly errors for new caps in the UI.
+
+Medium-term:
+
+- Add CI security checks for `govulncheck`, `npm audit --omit=dev`, and `git diff --check`.
+- Add release artifact checksums and an SBOM.
+
+Long-term:
+
+- Continue replacing dynamic frontend `innerHTML` where data provenance is mixed.
+- Add configurable large-download limits for GitHub archives and SFTP operations.
+
+## 19. False Positives / Needs Manual Verification
+
+- VNC Origin policy should be validated in macOS, Windows, and Linux packaged Wails builds.
+- The 2 GiB GitHub archive cap should be validated against expected user repository sizes.
+- The SSH keygen 30 second timeout should be checked on slow hardware, especially for RSA 4096.
+
+## 20. Final Notes
+
+This pass focused on concrete, testable hardening rather than broad speculative rewrites. The remaining risk is mostly runtime validation and UX around newly explicit limits. The repo still has an unrelated sidebar CSS spacing change in the working tree that was not part of this security audit.

audits/20260624-0945-functionalityNextSteps.md

@@ -0,0 +1,79 @@
+# Functionality and Next Steps Report
+
+## 1. Executive Summary
+
+This fix-mode pass improved VS Code extension robustness by hardening the local bridge and webview CSP handling. The highest-impact next step is runtime validation in a real VS Code host: the source-level tests pass, but the extension panels and long-lived bridge event stream deserve manual smoke coverage after the HTTP timeout and nonce changes.
+
+The codebase already has useful regression coverage for prior security fixes. The main opportunity now is to reduce duplicated webview HTML patterns and add integration tests around the VS Code bridge, because that surface currently depends heavily on static checks.
+
+## 2. Current Functional Risks
+
+- VS Code bridge `/events` uses a long-lived SSE stream. The new server has read/header/idle limits but intentionally no global write timeout, so a real VS Code smoke test should confirm events still flow correctly during SSH/SFTP/VNC/GitHub sessions.
+- VS Code webview HTML is duplicated across many panel classes. CSP, nonce generation, escaping, and message wiring are now correct in reviewed files, but duplication increases future regression risk.
+- The Node extension bridge client reads bridge responses without an explicit response-size cap or request timeout. The bridge is local and trusted, but a stuck bridge can still degrade the extension UX.
+- Frontend/webview coverage is mostly static regression assertions. It catches known bug patterns but does not prove that panels render and handlers fire inside VS Code.
+
+## 3. Code Quality Improvements
+
+- Centralise webview scaffolding in `vscode/nexus/extension.js` and `vscode/leviathan/extension.js`: CSP generation, nonce creation, common style policy, and HTML shell construction should live in one helper per extension or a shared local module.
+- Wrap bridge HTTP requests in a small client helper with timeout, response-size cap, JSON decode error handling, and consistent error messages.
+- Consider replacing large inline template-string webviews with smaller render helpers that build trusted static shell plus escaped dynamic content. The current approach is workable, but it makes security review repetitive.
+- Keep the bridge handler helpers small and testable. `newBridgeHTTPServer` and `decodeLimitedJSON` are a useful pattern for future endpoints.
+
+## 4. Frontend Interaction and Error-Handling Improvements
+
+- Add manual smoke steps for Nexus Connections, terminal, RAW, GitHub, IRC, VNC, Profile Editor, Settings, SFTP, Leviathan Tools, Leviathan Hex, and Leviathan tool panels.
+- Add non-sensitive `console.error` or visible status handling for JSON parse failures in VS Code webview message handlers where currently errors may be silent.
+- Validate that reconnect, resize, SFTP directory actions, GitHub refresh/download, and Leviathan tool execution still fire their expected events after panel reloads.
+- Confirm no webview logs secrets, bearer tokens, passwords, passphrases, private key material, or raw sensitive bridge responses.
+
+## 5. Testing Roadmap
+
+- Unit tests: keep `cmd/vscode-bridge` tests for server settings and body caps; add request method/auth tests for all bridge routes.
+- Integration tests: add socket-level bridge tests for slow headers, oversized headers, and idle connection cleanup.
+- VS Code extension smoke tests: exercise webview creation, command registration, bridge startup, one RPC, and one event frame.
+- Frontend interaction tests: use a browser/DOM harness for key Wails UI flows where practical, especially SFTP upload, profile import, SSH key management, and Leviathan mode switching.
+- Abuse-case tests: retain oversized import/upload/config tests and add edge cases whenever new parsers or bridge endpoints are introduced.
+- Release smoke tests: package VSIX files and assert expected files, CSP strings, media resources, and bridge executable permissions.
+
+## 6. Recommended New Functionality
+
+- Add an in-extension bridge diagnostics command that shows bridge status, version, last RPC error, and whether the event stream is connected, without exposing the bearer token.
+- Add a developer-only test command for the VS Code extension that opens each webview and posts a benign fixture state. This would make manual and automated smoke testing faster.
+- Add a small security status page or command that reports vault state, known-host policy, update-check source, and active local bridge address without sensitive values.
+
+## 7. Next-Level Opportunities
+
+- Create a shared webview rendering module for both Nexus and Leviathan extension panels, with typed helpers for CSP, escaping, buttons, and event wiring.
+- Introduce structured bridge RPC method allow-list metadata rather than reflective method dispatch alone. Reflection is convenient, but a visible allow-list would make the trust boundary easier to review.
+- Add observability around bridge request counts, rejected oversized requests, active event clients, and session lifecycle errors.
+- Add accessibility checks for VS Code webview panels, especially keyboard focus, button labels, and status updates in terminal/disconnected flows.
+
+## 8. Prioritised Action Plan
+
+Immediate:
+
+- Smoke-test the committed fix in a real VS Code host.
+- Confirm `/events` remains stable during session state changes.
+
+Short-term:
+
+- Add bridge client timeout and response-size caps in the Node extension code.
+- Add VS Code extension smoke tests for panel construction and bridge RPC.
+- Consolidate CSP nonce creation and webview HTML policy helpers.
+
+Medium-term:
+
+- Replace static-only regression assertions with executable DOM or VS Code integration tests for high-value panels.
+- Add bridge route coverage for auth failures, method errors, malformed JSON, and event subscription lifecycle.
+
+Long-term:
+
+- Build a release validation pipeline for desktop app, bridge binary, and VSIX packages.
+- Add structured diagnostics and observability for local bridge health and rejected requests.
+
+## 9. Caveats and Validation Needed
+
+- Source and automated tests passed, but VS Code runtime behaviour was not manually exercised in this pass.
+- The CSP nonce change should be behaviour-preserving, but every webview panel should still be opened once in VS Code.
+- The bridge timeout settings are conservative for local RPC; long-running operations should continue reporting progress through events rather than blocking a single HTTP request indefinitely.

audits/20260624-0945-securityAudit.md

@@ -0,0 +1,361 @@
+# Security Audit Report
+
+## 1. Executive Summary
+
+This fix-mode audit reviewed the Nexus desktop app, VS Code extensions, local bridge process, frontend regression harness, prior audit findings, dependency manifests, and build/test configuration. The codebase is in a materially better posture than the earlier June audits: major Wails, SFTP, VNC proxy, GitHub API, import-size, SSH key generation, and frontend DOM issues were already fixed and covered by tests.
+
+Two remaining issues were confirmed and fixed in commit `3a16a14`:
+
+- The VS Code bridge's localhost HTTP server had no explicit header/body read timeouts and decoded JSON request bodies without a hard cap.
+- VS Code webview CSP nonces were derived from `Date.now()`, which made a script allow-list nonce predictable rather than cryptographically random.
+
+Verification passed with targeted bridge tests, full Go tests, frontend regression checks, frontend build, `npm audit --omit=dev`, `govulncheck`, JavaScript syntax checks, and `git diff --check`.
+
+## 2. Scope Reviewed
+
+Reviewed:
+
+- Go backend packages under `internal/` and the `cmd/vscode-bridge` localhost JSON-RPC/SSE bridge.
+- Browser-facing frontend JavaScript and regression checks under `frontend/`.
+- VS Code extension webviews in `vscode/nexus/extension.js` and `vscode/leviathan/extension.js`.
+- Dependency manifests: `go.mod`, `go.sum`, `frontend/package.json`, `frontend/package-lock.json`, VS Code extension package manifests.
+- Build, release, and CI files including shell scripts and `.github/workflows/release-builds.yml`.
+- Existing audit reports under `audits/` to avoid duplicate findings.
+
+Not fully live-tested:
+
+- Packaged VS Code extensions inside a real VS Code host after the CSP nonce change.
+- Long-lived bridge event streams under deliberate slow-client conditions.
+- Packaged Wails binaries on all target operating systems.
+
+## 3. Methodology
+
+I used static review, adversarial attack-surface mapping, dependency review, configuration review, DoS review, frontend/webview review, and targeted regression tests. I traced attacker-controlled inputs from webviews, the VS Code extension host, local HTTP requests, imported files, remote services, and session events into filesystem, process, network, DOM, and parser boundaries.
+
+Commands run:
+
+- `node --check vscode/nexus/extension.js`
+- `node --check vscode/leviathan/extension.js`
+- `node --check frontend/scripts/test-regressions.js`
+- `go test ./cmd/vscode-bridge -count=1`
+- `npm --prefix frontend test`
+- `git diff --check`
+- `go test ./... -count=1`
+- `npm --prefix frontend run build`
+- `npm --prefix frontend audit --omit=dev`
+- `go run golang.org/x/vuln/cmd/govulncheck@latest ./...`
+
+## 4. Risk Rating Method
+
+Severity reflects attacker position, exploit practicality, affected trust boundary, and confidentiality/integrity/availability impact. Confidence reflects direct source evidence and regression coverage.
+
+- Critical: unauthenticated remote compromise or credential disclosure.
+- High: practical credential theft, code execution, or privilege escalation.
+- Medium: meaningful local, renderer, or connected-service abuse with realistic prerequisites.
+- Low: defence-in-depth or bounded local robustness issue.
+- Informational: hardening or validation gaps without a direct exploit path.
+
+## 5. Attack Surface Map
+
+Entry points:
+
+- Wails-bound API methods callable from the renderer.
+- VS Code extension webviews and their `postMessage` handlers.
+- `cmd/vscode-bridge` localhost HTTP endpoints: `/health`, `/rpc`, `/events`, and `/runtime/event`.
+- SSH, SFTP, Telnet, RAW TCP, VNC, GitHub, IRC, local shell, updater, recording, export/import, and Leviathan binary-analysis workflows.
+
+Trust boundaries:
+
+- Renderer/webview to Go backend.
+- Local browser or extension host to localhost bridge.
+- Local selected files and profile imports to parsers.
+- Remote GitHub, SSH/SFTP/VNC/IRC/Telnet/RAW endpoints to client code.
+- OS keychain/vault to profile/session runtime.
+
+Attacker starting positions considered:
+
+- Local unprivileged process attempting bridge resource exhaustion.
+- Malicious or compromised extension webview state.
+- Hostile remote service data rendered into webviews.
+- Malicious selected local file or imported profile/export.
+- Compromised connected host attempting terminal/session abuse.
+
+## 6. Findings Summary Table
+
+| ID | Severity | Confidence | Title | Component | Status |
+|---|---|---|---|---|---|
+| SEC-20260624-0945-001 | Low | High | VS Code bridge accepted unbounded HTTP parser work | `cmd/vscode-bridge` | Fixed in `3a16a14` |
+| SEC-20260624-0945-002 | Low | High | VS Code webview CSP nonces used predictable timestamps | `vscode/nexus`, `vscode/leviathan` | Fixed in `3a16a14` |
+
+## 7. Detailed Findings
+
+### Finding ID: SEC-20260624-0945-001
+
+#### Title
+
+VS Code bridge accepted unbounded HTTP parser work
+
+#### Severity
+
+Low
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `cmd/vscode-bridge/main.go:120`
+- `cmd/vscode-bridge/main.go:212`
+- `cmd/vscode-bridge/main.go:230`
+- `cmd/vscode-bridge/main.go:336`
+- `cmd/vscode-bridge/main.go:346`
+- `cmd/vscode-bridge/main_test.go:11`
+- `cmd/vscode-bridge/main_test.go:28`
+- `cmd/vscode-bridge/main_test.go:48`
+
+#### Description
+
+The bridge listens only on localhost and requires a random bearer token, but the HTTP server previously used default server timeouts and decoded JSON bodies directly from `r.Body`. A local process, or a compromised component with bridge token access, could keep connections open or send oversized JSON to force unnecessary parser work and memory use.
+
+#### Evidence
+
+Before the fix, `server := &http.Server{Handler: mux}` used default timeout values, and `/rpc` plus `/runtime/event` called `json.NewDecoder(r.Body).Decode(...)` without `http.MaxBytesReader`.
+
+The fix adds explicit bridge limits at `cmd/vscode-bridge/main.go:50`, uses `newBridgeHTTPServer` at `cmd/vscode-bridge/main.go:126`, and applies `decodeLimitedJSON` in both POST handlers at `cmd/vscode-bridge/main.go:218` and `cmd/vscode-bridge/main.go:236`.
+
+#### Attack Scenario
+
+A local unprivileged process repeatedly connects to the bridge and sends slow headers or a large authenticated JSON body. Without timeouts and body caps, the bridge can spend disproportionate time and memory on unauthorised or oversized traffic.
+
+#### Impact
+
+Local denial of service against the VS Code extension bridge, causing sluggishness, failed RPCs, or event-stream disruption.
+
+#### Recommendation
+
+Set bounded HTTP server timeouts and header limits. Cap JSON request bodies before decoding. Keep long-lived SSE compatibility by avoiding a global `WriteTimeout` that would break event streams.
+
+#### Safer Example
+
+Implemented:
+
+```go
+r.Body = http.MaxBytesReader(w, r.Body, bridgeMaxJSONBodyBytes)
+return json.NewDecoder(r.Body).Decode(dst)
+```
+
+#### Suggested Tests
+
+Added tests that assert bridge timeout/header settings and oversized `/rpc` plus `/runtime/event` bodies are rejected before reflective service dispatch.
+
+#### References
+
+- CWE-400: Uncontrolled Resource Consumption
+- OWASP ASVS 12.1: File and resource handling
+- OWASP API Security Top 10 API4: Unrestricted Resource Consumption
+
+#### Assumptions / Limitations
+
+The practical attacker is local, because the bridge binds to `127.0.0.1`. The bearer token remains an important control, but it is not a substitute for parser and server resource limits.
+
+### Finding ID: SEC-20260624-0945-002
+
+#### Title
+
+VS Code webview CSP nonces used predictable timestamps
+
+#### Severity
+
+Low
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `vscode/nexus/extension.js:5`
+- `vscode/nexus/extension.js:10`
+- `vscode/nexus/extension.js:219`
+- `vscode/nexus/extension.js:554`
+- `vscode/nexus/extension.js:895`
+- `vscode/nexus/extension.js:1061`
+- `vscode/nexus/extension.js:1162`
+- `vscode/nexus/extension.js:1260`
+- `vscode/nexus/extension.js:1375`
+- `vscode/nexus/extension.js:1618`
+- `vscode/nexus/extension.js:1832`
+- `vscode/leviathan/extension.js:5`
+- `vscode/leviathan/extension.js:10`
+- `vscode/leviathan/extension.js:189`
+- `vscode/leviathan/extension.js:497`
+- `vscode/leviathan/extension.js:773`
+- `frontend/scripts/test-regressions.js:222`
+
+#### Description
+
+The VS Code webviews use CSP script nonces, but each nonce was previously `String(Date.now())`. CSP nonces are intended to be high-entropy, per-render allow-list values. A timestamp nonce is guessable and weakens CSP if an HTML injection primitive is introduced elsewhere.
+
+#### Evidence
+
+All `const nonce = String(Date.now());` occurrences in the VS Code extension files were replaced with `createCSPNonce()`, backed by `crypto.randomBytes(16).toString('base64')`.
+
+#### Attack Scenario
+
+An attacker finds or later introduces a webview HTML injection path that can emit a `<script nonce="...">` tag. A predictable timestamp nonce materially reduces the barrier to bypassing CSP, especially when the webview creation time is observable or inferable.
+
+#### Impact
+
+Defence-in-depth weakness for webview script execution controls. A full exploit still requires an injection path, but predictable nonces undermine the CSP layer that should contain that class of defect.
+
+#### Recommendation
+
+Generate CSP nonces with cryptographically secure random bytes for every webview render, and keep regression coverage preventing timestamp nonce reintroduction.
+
+#### Safer Example
+
+Implemented:
+
+```js
+function createCSPNonce() {
+  return crypto.randomBytes(16).toString('base64');
+}
+```
+
+#### Suggested Tests
+
+Added regression assertions that both VS Code extension files use `crypto.randomBytes(16).toString('base64')` and that `const nonce = String(Date.now());` is absent under `vscode/`.
+
+#### References
+
+- CWE-345: Insufficient Verification of Data Authenticity
+- CWE-693: Protection Mechanism Failure
+- OWASP ASVS 14.4: Security headers
+
+#### Assumptions / Limitations
+
+I did not confirm a current exploitable webview injection path in these files during this pass. This fix preserves the CSP guarantee if a future DOM/HTML bug appears.
+
+## 8. Blackhat-Style Abuse Paths
+
+Path 1: Local bridge exhaustion.
+
+Prerequisite: local code execution on the same machine. The attacker opens many slow or oversized bridge requests. Before the fix, default server settings and uncapped JSON decoding provided weaker resistance. Defensive breakpoint: `ReadHeaderTimeout`, `ReadTimeout`, `IdleTimeout`, `MaxHeaderBytes`, and `http.MaxBytesReader`.
+
+Path 2: Future webview injection to script execution.
+
+Prerequisite: an HTML injection sink in a VS Code webview. Predictable CSP nonces made it easier to craft a nonce-bearing script. Defensive breakpoint: cryptographic per-render nonces and continued escaping/text-node rendering.
+
+## 9. Denial-of-Service Review
+
+Fixed:
+
+- Local bridge header/body parsing now has explicit limits.
+- Oversized bridge JSON bodies are rejected before reflective RPC dispatch.
+
+Previously fixed and still covered by tests:
+
+- VNC WebSocket frame read limits.
+- SFTP upload chunk and streaming size controls.
+- SSH config import file and Host-block caps.
+- GitHub archive stream cap.
+- Update response caps.
+- Leviathan and recording file-size limits in reviewed paths.
+
+Residual DoS considerations:
+
+- Long-lived `/events` streams intentionally remain open; they should be observed under slow-client conditions in VS Code.
+- Remote SFTP operations still rely on remote server responsiveness and transport-level behaviour.
+- Binary-analysis features should continue adding per-tool time and output caps as new parsers are added.
+
+## 10. Dependency and Supply-Chain Review
+
+`npm --prefix frontend audit --omit=dev` reported zero production vulnerabilities. `govulncheck` reported no reachable Go vulnerabilities. The release workflow uses pinned major versions of common GitHub Actions but still installs Wails dynamically from the module version; that is acceptable but should be monitored in release hardening.
+
+## 11. Secrets and Sensitive Data Review
+
+No new hard-coded credentials or private keys were found in the changed files. The bridge token remains generated with `crypto/rand` and is emitted to the extension process over stdout. Secret storage continues to use OS keychain and encrypted vault mechanisms reviewed in earlier audits.
+
+## 12. Authentication and Authorisation Review
+
+The bridge still requires `Authorization: Bearer <token>`. The fix does not change bridge authorisation semantics. No new auth bypass was identified in this pass. Host key handling, SFTP path validation, GitHub URL validation, and profile validation had existing regression coverage from prior fixes.
+
+## 13. Input Validation and Output Encoding Review
+
+Fixed:
+
+- Bridge JSON input is bounded to 1 MiB before decoding.
+
+Checked:
+
+- VS Code webviews continue escaping interpolated profile, repository, SFTP, and Leviathan state before `innerHTML` usage in reviewed areas.
+- Frontend regression tests include prior checks for SSH key manager error rendering and SFTP upload name handling.
+
+## 14. Frontend HTML/JavaScript Robustness Review
+
+Fixed:
+
+- VS Code webview CSP nonces are now cryptographically random.
+
+Checked:
+
+- Existing frontend regression script still passes.
+- JavaScript syntax checks pass for both VS Code extension files and the regression script.
+
+Manual validation still needed:
+
+- Open the Nexus and Leviathan VS Code webviews in a real VS Code host and confirm all panels load under the stricter nonce generation.
+
+## 15. Infrastructure and Deployment Review
+
+The GitHub Actions release workflow was reviewed for obvious command injection or secret leakage. No new finding was fixed here. It still uses broad `contents: write` permissions for release attachment, which is appropriate for the release job but should remain isolated to tag/manual workflows.
+
+## 16. Logging, Monitoring, and Error Handling Review
+
+Bridge oversized-body failures return structured JSON errors through the existing RPC error path. No sensitive values are logged by the new code. The bridge still logs startup/server failures through `log`.
+
+## 17. Test Coverage and Security Regression Gaps
+
+Added:
+
+- Bridge server resource-limit tests.
+- Oversized `/rpc` body test.
+- Oversized `/runtime/event` body test.
+- Regression assertions preventing timestamp CSP nonces in VS Code webviews.
+
+Remaining gaps:
+
+- No automated VS Code host integration test exercises all webview panels.
+- No slowloris-style integration test measures bridge timeout behaviour over real sockets.
+- No e2e test validates the long-lived SSE event stream after server timeout changes.
+
+## 18. Prioritised Remediation Plan
+
+Immediate:
+
+- Manually smoke-test the packaged VS Code extension panels and bridge event stream.
+
+Short-term:
+
+- Add a small VS Code extension integration smoke test for webview creation and bridge RPC.
+- Add a socket-level bridge test for slow headers and idle connections.
+
+Medium-term:
+
+- Centralise VS Code webview HTML helpers so CSP, escaping, and nonce generation are not duplicated.
+- Add response-size caps and request timeouts in the Node extension bridge client.
+
+Long-term:
+
+- Add release-time security checks for packaged VSIX contents, binary hashes, and expected CSP coverage.
+
+## 19. False Positives / Needs Manual Verification
+
+- The CSP nonce issue is a defence-in-depth finding, not evidence of a currently exploitable XSS.
+- Bridge DoS impact is local because the bridge binds to localhost.
+- VS Code runtime behaviour was not manually validated inside the actual editor during this audit.
+
+## 20. Final Notes
+
+The confirmed issues were fixed and committed in `3a16a14`. The residual risk is mainly operational validation: verify the VS Code extension panels in a real host and keep expanding integration coverage for bridge and webview behaviour.

audits/20260729-1237-functionalityNextSteps.md

@@ -0,0 +1,197 @@
+# Functionality and Next Steps Report
+
+## 1. Executive Summary
+
+This fix-mode pass makes long-running Nexus processes more predictable:
+reconnect prompts no longer accumulate runtime listeners, unfinished SFTP
+uploads are bounded and cancelled with their owning sessions, and application
+shutdown drains prompt, listener, session, and upload state. IPv6 literals now
+work in the reviewed VNC, IRC tunnel, and connection-test paths.
+
+The full backend, race, frontend, build, syntax, and dependency checks pass.
+The highest-value next step is a packaged long-duration soak test using real
+local and remote tabs. Unit tests prove the new ownership rules, but only a live
+test will show whether CPU, memory, goroutine, descriptor, and remote-session
+counts remain flat across thousands of open/close/reconnect cycles.
+
+## 2. Current Functional Risks
+
+- Application-level cleanup is now explicit, but remote libraries and OS
+  resources need live soak validation with real SSH, SFTP, VNC, IRC, Telnet,
+  RAW, and local shell sessions.
+- SFTP partial-file removal is best-effort. If a transport is already dead,
+  Nexus can close its local writer but may be unable to remove the remote
+  partial file.
+- External Leviathan extractors can run subprocesses without a shared timeout,
+  output-byte cap, or file-count cap. This path should remain unexposed until
+  those controls exist.
+- Parser test coverage varies by format. Complex hostile files may still find
+  correctness or performance edge cases not represented by current fixtures.
+- Several frontend areas still render trusted templates through `innerHTML`.
+  Existing dynamic values are escaped in reviewed paths, but DOM-based
+  construction would be less fragile for future edits.
+- Four Go module versions have advisories in code paths Nexus does not call.
+  They are not current reachable vulnerabilities, but routine dependency
+  refresh will reduce future uncertainty.
+- POSIX permission tests do not establish equivalent Windows ACL behaviour.
+
+## 3. Code Quality Improvements
+
+- Make ownership visible in types and naming. Sessions should own reconnect
+  contexts, uploads, protocol clients, terminal resources, and timers through a
+  single idempotent close path.
+- Introduce a small lifecycle registry for application-level Wails listeners.
+  The new stored unsubscribe functions are correct; a shared helper would make
+  future listeners harder to leak.
+- Replace `time.After` in long-lived or high-frequency paths with owned timers
+  when cancellation or reuse matters. The current reconnect prompt has bounded
+  frequency, but an owned timer makes resource lifetime more explicit.
+- Return structured cleanup results for unfinished uploads: local writer
+  closed, remote partial removed, or remote removal unavailable. This would
+  improve diagnostics without turning cleanup failure into a tab-close
+  blocker.
+- Centralise network endpoint formatting so every protocol consistently uses
+  `net.JoinHostPort` and one port-validation helper.
+- Keep frontend regression assertions aligned with tracked source. The audit
+  removed assertions for the intentionally deleted VS Code tree and replaced
+  the obsolete CGO flag check with the current pure-Go invariant.
+
+## 4. Frontend Interaction and Error-Handling Improvements
+
+- When a tab closes during an upload, display a brief non-blocking message that
+  the upload was cancelled and whether a remote partial file may remain.
+- Make credential-prompt cancellation explicit in the UI so a reconnect
+  cancellation is distinguishable from a wrong password or timeout.
+- Add an unobtrusive diagnostics panel showing counts only: open tabs, active
+  protocol sessions, reconnect workers, pending prompts, streaming uploads,
+  goroutines, and recent cleanup failures.
+- Disable or debounce reconnect controls while a reconnect is already in
+  progress.
+- Prefer `textContent`, element creation, and event delegation for dynamic UI
+  state. Keep `innerHTML` for reviewed static templates only.
+- Ensure every async action rechecks that its tab/session still exists before
+  updating the DOM. This prevents late remote responses from reviving stale
+  state or producing confusing errors.
+- Never put passwords, vault contents, tokens, private keys, bridge tokens, or
+  terminal contents in diagnostics or frontend logs.
+
+## 5. Testing Roadmap
+
+Immediate automated coverage:
+
+- Add tests that call `Service.Shutdown` and `Manager.Shutdown` twice to enforce
+  idempotence.
+- Add a race test where an SFTP chunk write, session close, and shutdown overlap.
+- Add tests for a capacity race where two upload starts pass the pre-check and
+  only one may claim the final slot.
+- Add address-table tests for IPv4, DNS names, bare IPv6, and scoped IPv6
+  literals.
+
+Packaged soak coverage:
+
+- Start with zero tabs and record CPU, RSS, goroutines, descriptors, and
+  listener/upload counts.
+- Repeat local terminal open/write/close and SSH open/reconnect/close at least
+  1,000 times.
+- Repeat cancelled credential prompts and interrupted SFTP uploads.
+- Leave two idle tabs open for several hours and confirm resource counts and
+  CPU settle rather than grow.
+- Shut down and verify all subprocesses, sockets, PTYs, uploads, and runtime
+  listeners terminate.
+
+Protocol integration coverage:
+
+- Real SFTP server: finish, cancel, disconnect mid-chunk, reconnect, dead
+  transport, and remote partial-file cleanup.
+- Real IPv6 endpoints for VNC and SSH-tunnelled IRC/VNC.
+- Host-key accept/reject/cancel and secret prompt cancel/timeout.
+- Slow or malicious peers for protocol read limits and cancellation.
+
+Parser and frontend coverage:
+
+- Fuzz the PE, ELF, Mach-O, SquashFS, PDF, archive, and transform entry points.
+- Add DOM tests for tab close during asynchronous callbacks.
+- Keep `npm test`, frontend build, `go vet`, focused race tests,
+  `govulncheck`, and `npm audit` as release gates.
+
+## 6. Recommended New Functionality
+
+- Add a resource diagnostics view with current and peak counts for tabs,
+  sessions, reconnects, prompts, uploads, goroutines, file descriptors where
+  available, and local child processes.
+- Add an optional "delete partial remote upload on disconnect" status/history
+  entry, including a retry action after reconnect.
+- Add a developer soak command that scripts repeated open/reconnect/close
+  cycles against safe fixture servers and emits a machine-readable resource
+  summary.
+- Add an export-permission warning when the destination filesystem cannot
+  enforce private file access.
+- Add a dependency-health command for development builds that reports the Go
+  toolchain version and last audit result without contacting external services
+  during normal application use.
+
+## 7. Next-Level Opportunities
+
+- Build one lifecycle coordinator that owns application listeners, service
+  uploads, sessions, reconnect workers, protocol clients, timers, and local
+  subprocesses. A small dependency graph would make shutdown ordering
+  testable.
+- Add pprof-enabled development builds and automated before/after heap,
+  goroutine, mutex, and CPU profile comparisons during soak tests.
+- Introduce fault injection around remote writes, EOF, connection resets,
+  prompt cancellation, delayed events, and shutdown.
+- Wrap external analysis tools in a sandbox-oriented runner with a context
+  deadline, process-group kill, private working directory, output byte/file
+  limits, and a minimal environment.
+- Add signed, reproducible release metadata and verify the expected Go
+  toolchain, module graph, frontend lock file, and artefact hashes in CI.
+
+## 8. Prioritised Action Plan
+
+Immediate:
+
+- Run a packaged local/remote tab soak test and capture resource graphs before
+  and after `b5c7528`.
+- Validate interrupted SFTP uploads against a real server.
+- Confirm shutdown leaves no Nexus child process, PTY, listener, or open
+  connection.
+
+Short-term:
+
+- Add shutdown-idempotence and overlapping upload/close race tests.
+- Add resource counters and a development diagnostics view.
+- Refresh modules with unreachable advisories under a dedicated compatibility
+  change.
+- Add live IPv6 integration tests.
+
+Medium-term:
+
+- Add parser fuzzing and external extractor limits.
+- Reduce dynamic HTML construction and add DOM lifecycle tests.
+- Add fault-injected protocol integration tests.
+
+Long-term:
+
+- Make packaged soak, vulnerability, dependency, race, and artefact checks part
+  of release qualification.
+- Track resource-count baselines so gradual lifecycle regressions fail before
+  release.
+
+## 9. Caveats and Validation Needed
+
+- Automated checks passed, but no packaged Wails application was opened during
+  this audit.
+- No real remote protocol server was used, so remote partial-file behaviour and
+  third-party client cleanup still need live confirmation.
+- The CPU symptom was not reproduced under a profiler in this pass. The
+  reconnect listener leak and upload leak were confirmed from source and fixed,
+  but they should not be claimed as the only possible causes of historical
+  high CPU without a profile from an affected long-running process.
+- Filesystem permission behaviour was validated on the current POSIX host, not
+  Windows ACLs or every network filesystem.
+- `clear` reduces the lifetime of mutable sensitive byte slices but does not
+  guarantee complete memory erasure in Go.
+- `govulncheck` reports no reachable vulnerability after the toolchain update;
+  its four module-only advisories still deserve normal upgrade testing.
+- The deleted VS Code extension sources were not audited as current code. Only
+  the still-tracked Go bridge was reviewed.

audits/20260729-1237-securityAudit.md

@@ -0,0 +1,858 @@
+# Security Audit Report
+
+## 1. Executive Summary
+
+This fix-mode audit reviewed the current Nexus desktop application, its local
+VS Code bridge process, browser-facing frontend, session and upload lifecycles,
+credential handling, network clients, encrypted storage and export, Leviathan
+file analysis, build/release configuration, dependencies, and earlier audit
+reports.
+
+No Critical or High severity vulnerability was confirmed. Four
+evidence-backed findings were fixed in commit `b5c7528`:
+
+- Auto-reconnect credential prompts registered a permanent Wails listener on
+  every prompt. Long-running processes with repeated reconnects accumulated
+  callbacks and unnecessary event-dispatch work.
+- Interrupted streaming SFTP uploads could retain open remote writers and
+  in-memory upload entries after their session closed. Concurrent unfinished
+  uploads were not bounded.
+- The accepted Go toolchain range included versions affected by a reachable
+  standard-library TLS privacy vulnerability.
+- Encrypted exports and Leviathan carve output did not consistently enforce
+  private local file permissions. Short-lived plaintext and derived key byte
+  slices were also retained until garbage collection.
+
+The same commit fixed malformed IPv6 host/port construction in VNC, IRC SSH
+tunnels, and the connection tester, and repaired stale frontend regression
+assertions left behind when the VS Code extension tree and CGO build were
+removed.
+
+All Go tests, focused race tests, Go vet, the complete frontend test suite,
+frontend production build, JavaScript and shell syntax checks, PHP syntax
+check, `npm audit`, and the reachable Go vulnerability scan pass. Live remote
+protocol testing and packaged desktop testing remain manual validation items.
+
+## 2. Scope Reviewed
+
+Reviewed:
+
+- Go packages under `internal/`, including sessions, SSH, SFTP, VNC, IRC,
+  Telnet, RAW TCP, local shells, storage, vault/keychain integration,
+  recording, updater, GitHub client, import/export, and Leviathan.
+- The localhost service bridge in `cmd/vscode-bridge`.
+- Frontend source, lifecycle handling, DOM construction, timers, Wails event
+  subscriptions, build scripts, and regression harness under `frontend/`.
+- Network address construction, host-key verification, connection setup, and
+  session shutdown paths.
+- Dependency manifests and lock files.
+- Build, release, update, and CI configuration.
+- Earlier reports under `audits/`, to distinguish regressions from already
+  fixed findings.
+
+Not live-tested:
+
+- Packaged Wails applications on every supported operating system.
+- Real SSH, SFTP, VNC, IRC, Telnet, RAW, GitHub, or update endpoints.
+- Malicious network peers under sustained load.
+- External Leviathan extractor tools. Their extraction path is not currently
+  exposed by the active Wails document response.
+- A VS Code extension runtime, because the `vscode/` source tree was
+  intentionally removed in commit `4fc3b19`.
+
+## 3. Methodology
+
+The review combined:
+
+- Repository and Git-history inspection.
+- Trust-boundary and attacker-starting-position mapping.
+- Static review of authentication, authorisation, secrets, cryptography,
+  filesystem operations, command execution, parsers, network clients, event
+  listeners, goroutines, timers, and cleanup paths.
+- Adversarial resource-exhaustion review, with particular attention to a
+  process that has run for a long time while tabs and sessions are repeatedly
+  opened, reconnected, and closed.
+- Frontend sink/source review for unsafe HTML, event-listener accumulation,
+  timers, stale state, and privileged Wails calls.
+- Dependency and supply-chain scanning.
+- Focused regression tests followed by broad test, race, build, syntax, and
+  static-analysis checks.
+
+Principal validation commands:
+
+- `go test ./... -count=1`
+- `go test -race ./internal/sessions ./internal/api ./internal/exportimport ./internal/vncclient ./cmd/vscode-bridge -count=1`
+- `go vet ./...`
+- `go run golang.org/x/vuln/cmd/govulncheck@latest -show verbose ./...`
+- `go run github.com/securego/gosec/v2/cmd/gosec@latest ./...`
+- `npm test` in `frontend/`
+- `npm run build` in `frontend/`
+- `npm audit --json` in `frontend/`
+- `node --check` for changed JavaScript
+- `bash -n build.sh build-all.sh release.sh scripts/build-common.sh`
+- `php -l updates/index.php`
+- `git diff --check`
+
+## 4. Risk Rating Method
+
+Severity reflects attacker position, prerequisites, exploit repeatability,
+trust-boundary impact, and confidentiality, integrity, and availability
+consequences.
+
+- Critical: practical unauthenticated remote compromise or broad secret
+  disclosure.
+- High: practical code execution, credential theft, or privilege escalation.
+- Medium: meaningful local, renderer, connected-peer, or privacy impact with
+  realistic prerequisites.
+- Low: bounded local exposure, defence-in-depth weakness, or correctness issue
+  with a security consequence.
+- Informational: hardening or validation work without a confirmed exploit.
+
+Confidence reflects the strength of source evidence, reproduction, scanner
+evidence, and regression coverage. Severity is not increased merely because a
+scanner reports a possible pattern.
+
+## 5. Attack Surface Map
+
+Entry points:
+
+- Wails-bound service methods invoked by the desktop renderer.
+- Runtime events crossing between frontend JavaScript and Go.
+- The token-authenticated localhost bridge endpoints.
+- User-selected SSH, SFTP, VNC, IRC, Telnet, RAW TCP, GitHub, and update
+  endpoints.
+- Imported profiles, OpenSSH configuration, encrypted Nexus exports,
+  recordings, and files selected for Leviathan analysis.
+- Local shell commands and SSH key generation.
+
+Trust boundaries:
+
+- Renderer to privileged Go backend.
+- Local bridge client to localhost HTTP/RPC service.
+- OS keychain or encrypted vault to runtime session credentials.
+- Remote network data to protocol clients and frontend rendering.
+- User-selected or hostile files to parsers and external analysis tooling.
+- Release workflow and update manifest to installed application binaries.
+
+Attacker starting positions considered:
+
+- A malicious or compromised remote service.
+- A hostile local file or imported configuration.
+- A local unprivileged process targeting the localhost bridge or filesystem
+  artefacts.
+- A renderer injection or future renderer compromise invoking bound methods.
+- An observer of TLS traffic.
+- A legitimate local user accidentally creating unbounded resource state over
+  a long-running process.
+
+## 6. Findings Summary Table
+
+| ID | Severity | Confidence | Title | Component | Status |
+|---|---|---|---|---|---|
+| SEC-20260729-1237-001 | Medium | High | Reconnect credential prompts accumulated permanent runtime listeners | `internal/sessions` | Fixed in `b5c7528` |
+| SEC-20260729-1237-002 | Medium | High | Interrupted SFTP uploads retained resources without a concurrency bound | `internal/api` | Fixed in `b5c7528` |
+| SEC-20260729-1237-003 | Medium | High | Build accepted a Go toolchain with a reachable TLS privacy vulnerability | `go.mod`, build scripts | Fixed in `b5c7528` |
+| SEC-20260729-1237-004 | Low | High | Sensitive local artefacts did not consistently enforce private permissions | Export/import and Leviathan | Fixed in `b5c7528` |
+
+## 7. Detailed Findings
+
+### Finding ID: SEC-20260729-1237-001
+
+#### Title
+
+Reconnect credential prompts accumulated permanent runtime listeners
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/sessions/manager.go:110`
+- `internal/sessions/manager.go:676`
+- `internal/sessions/manager.go:2577`
+- `internal/sessions/manager.go:2615`
+- `internal/sessions/manager.go:2654`
+- `internal/sessions/manager_test.go:383`
+- `cmd/vscode-bridge/main.go:187`
+- `internal/app/app.go:118`
+
+#### Description
+
+Every credential request created during automatic reconnect registered another
+`session:secret:response` Wails listener. The listener was never unregistered,
+including after a response, timeout, cancelled reconnect, session close, or
+application shutdown.
+
+The request ID check prevented one prompt from accepting another prompt's
+value, but all historical callbacks were still invoked for every future
+credential response. A process left open for a long time could therefore
+accumulate event callbacks in proportion to its reconnect history. A closed
+session could also leave a credential prompt waiting for its full timeout.
+
+#### Evidence
+
+Before the fix, `buildInteractiveSecretCallback` called
+`wailsRuntime.EventsOn` inside the callback created for each prompt and
+discarded the returned unsubscribe function.
+
+The fix registers one manager-level response router from `SetContext`, stores
+the unsubscribe function, routes responses through a request-ID map, honours
+frontend cancellation, and selects on the reconnect context. `Shutdown`
+unregisters both host-key and credential listeners and releases all waiters.
+Application and bridge shutdown now call the complete service and manager
+shutdown methods.
+
+#### Attack Scenario
+
+A remote SSH or IRC service repeatedly drops connections after authentication,
+or a user repeatedly opens and reconnects profiles that require an interactive
+secret. Historical event listeners accumulate. Later secret responses fan out
+to all callbacks, increasing CPU work and retained memory even though old tabs
+are closed.
+
+#### Impact
+
+Progressive memory and CPU consumption in a long-running process, sluggish
+credential prompts, delayed shutdown, and eventual application availability
+loss. The request-ID routing means no cross-session secret disclosure was
+confirmed.
+
+#### Recommendation
+
+Use one application-lifetime event listener per event type, route responses by
+opaque request ID, bind every waiter to a cancellation context, and explicitly
+unsubscribe and release waiters during shutdown.
+
+#### Safer Example
+
+Implemented in outline:
+
+```go
+cancel := wailsRuntime.EventsOn(ctx, "session:secret:response", m.handleSecretResponse)
+m.secretListenerCancel = cancel
+
+select {
+case response := <-ch:
+    return response.value, cancellationError(response)
+case <-ctx.Done():
+    return "", ctx.Err()
+}
+```
+
+#### Suggested Tests
+
+Added tests verify request-ID routing, reconnect-context cancellation, frontend
+cancellation, pending-map cleanup, and shutdown waiter release. The focused
+race suite passes.
+
+#### References
+
+- CWE-400: Uncontrolled Resource Consumption
+- CWE-772: Missing Release of Resource after Effective Lifetime
+
+#### Assumptions / Limitations
+
+No packaged Wails runtime stress test was run. The defect and fix are directly
+visible in source, and the routing/cancellation logic is covered at Go level.
+
+### Finding ID: SEC-20260729-1237-002
+
+#### Title
+
+Interrupted SFTP uploads retained resources without a concurrency bound
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/api/api.go:52`
+- `internal/api/api.go:117`
+- `internal/api/api.go:469`
+- `internal/api/api.go:475`
+- `internal/api/api.go:515`
+- `internal/api/api.go:1569`
+- `internal/api/api.go:2189`
+- `internal/api/api.go:2202`
+- `internal/api/api_test.go:145`
+
+#### Description
+
+Streaming SFTP upload state held an open remote writer in the service upload
+map. Finish and explicit cancel removed it, but disconnecting, reconnecting, or
+closing the owning session did not. Application shutdown also did not drain
+unfinished uploads. There was no limit on the number of simultaneously open
+streaming uploads.
+
+#### Evidence
+
+The earlier lifecycle paths called the session manager directly without
+visiting the upload map. `SFTPUploadStart` inserted every new writer without a
+capacity check.
+
+The fix:
+
+- Caps active streaming uploads at 16.
+- Checks capacity before opening a remote writer and atomically rechecks before
+  insertion.
+- Removes and closes uploads belonging to a session before disconnect or
+  reconnect.
+- Drains every upload during close-all and service shutdown.
+- Best-effort removes the partial remote file.
+- Releases secret-prompt waiters and the service's Wails listener during
+  shutdown as part of the same lifecycle hardening.
+
+#### Attack Scenario
+
+A compromised renderer, automation loop, or repeated user action starts
+uploads and closes the associated tabs or sessions without finishing them.
+Each iteration can retain a local map entry, SFTP request state, remote file
+handle, and partially written file. Repetition eventually exhausts descriptors,
+memory, or server-side resources.
+
+#### Impact
+
+Local and remote resource exhaustion, failed subsequent uploads, leaked partial
+files, and degraded session availability.
+
+#### Recommendation
+
+Make resource ownership explicit: uploads must be owned by a session and
+cancelled when that session ends. Bound concurrent work and keep a race-safe
+second capacity check after expensive setup.
+
+#### Safer Example
+
+Implemented:
+
+```go
+func (s *Service) DisconnectSession(sessionID string) error {
+    s.cancelSFTPUploads(sessionID)
+    return s.sessions.Disconnect(sessionID)
+}
+```
+
+#### Suggested Tests
+
+Added tests verify session-scoped cancellation, unrelated-upload preservation,
+the active-upload limit, writer closure, and shutdown cleanup. Full and race
+tests pass.
+
+#### References
+
+- CWE-400: Uncontrolled Resource Consumption
+- CWE-404: Improper Resource Shutdown or Release
+- CWE-772: Missing Release of Resource after Effective Lifetime
+
+#### Assumptions / Limitations
+
+No real SFTP server was used to verify partial-file deletion after a transport
+failure. Removal is best-effort because the session may already be unavailable;
+local writer and map cleanup do not depend on remote deletion succeeding.
+
+### Finding ID: SEC-20260729-1237-003
+
+#### Title
+
+Build accepted a Go toolchain with a reachable TLS privacy vulnerability
+
+#### Severity
+
+Medium
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `go.mod:3`
+- `go.mod:5`
+- `build.sh:21`
+- `build-all.sh:20`
+
+#### Description
+
+The build accepted Go 1.25.0 and the local build used Go 1.26.4.
+`govulncheck` identified GO-2026-5856 / CVE-2026-42505 in a reachable
+`crypto/tls` path. Affected clients could expose TLS PSK identities in a
+plaintext ClientHello while Encrypted Client Hello was in use, allowing a
+passive observer to undermine ECH privacy.
+
+#### Evidence
+
+The pre-fix scan reported the standard-library vulnerability as reachable.
+The [official Go vulnerability record](https://pkg.go.dev/vuln/GO-2026-5856)
+states that Go 1.25 is fixed in 1.25.12 and Go 1.26 is fixed in 1.26.5.
+
+The fix raises the module minimum to Go 1.25.12, requests toolchain Go 1.26.5,
+and aligns both Unix build scripts with the new minimum. The post-fix verbose
+scan used the Go 1.26.5 standard library and reported zero symbol or package
+vulnerabilities affecting Nexus.
+
+#### Attack Scenario
+
+Where ECH and PSK resumption are used, a passive network observer records the
+client's plaintext ClientHello and correlates an exposed PSK identity with the
+protected destination.
+
+#### Impact
+
+Conditional network privacy disclosure. No private key or application
+credential extraction was demonstrated. Nexus does not explicitly configure
+ECH, so actual exposure depends on TLS configuration and runtime behaviour.
+
+#### Recommendation
+
+Enforce fixed toolchain floors in `go.mod`, local build scripts, and CI. Keep
+`govulncheck` in release validation so standard-library vulnerabilities cannot
+be missed by module-only scanners.
+
+#### Safer Example
+
+Implemented:
+
+```text
+go 1.25.12
+toolchain go1.26.5
+```
+
+#### Suggested Tests
+
+Run `go version` and verbose `govulncheck` in release CI, and fail if a
+reachable symbol-level vulnerability is reported.
+
+#### References
+
+- GO-2026-5856
+- CVE-2026-42505
+- CWE-200: Exposure of Sensitive Information
+
+#### Assumptions / Limitations
+
+The scanner established a reachable TLS symbol path, not that Nexus actively
+negotiated ECH with a vulnerable server during this audit. Severity therefore
+reflects conditional exploitability.
+
+### Finding ID: SEC-20260729-1237-004
+
+#### Title
+
+Sensitive local artefacts did not consistently enforce private permissions
+
+#### Severity
+
+Low
+
+#### Confidence
+
+High
+
+#### Affected Files / Components
+
+- `internal/exportimport/exportimport.go:68`
+- `internal/exportimport/exportimport.go:111`
+- `internal/exportimport/exportimport.go:116`
+- `internal/exportimport/exportimport.go:170`
+- `internal/exportimport/exportimport_test.go:108`
+- `internal/leviathan/binsnoop/binsnoop.go:137`
+- `internal/leviathan/binsnoop/binsnoop.go:141`
+- `internal/leviathan/binsnoop/extract.go:17`
+- `internal/leviathan/binsnoop/extract.go:20`
+- `internal/leviathan/binsnoop/common_test.go:25`
+
+#### Description
+
+Encrypted profile exports were created through `os.Create`, which normally
+uses mode `0666` filtered by the process umask. Overwriting an existing file
+also preserved its existing mode. Leviathan carved binary data and extraction
+directories used `0644` and `0755`. Carved content can include credentials,
+private keys, firmware configuration, or other forensic secrets.
+
+Export encryption keys, password byte slices, and decrypted plaintext byte
+slices also remained live until garbage collection after use.
+
+#### Evidence
+
+The fix opens exports with mode `0600` and explicitly applies `Chmod(0600)` so
+an existing permissive destination is tightened. Leviathan-owned carve files
+now use `0600`, and directories use `0700`. Export/import makes a best-effort
+`clear` of transient password, derived-key, and plaintext byte slices.
+
+#### Attack Scenario
+
+On a multi-user host, another local account reads a carved private key or
+configuration from a world-readable output file. For an export destination
+that already had permissive permissions, another account can copy the
+encrypted profile bundle for offline password guessing.
+
+#### Impact
+
+Local confidentiality exposure. The export remains protected by Argon2id and
+AES-GCM, which significantly reduces its immediate sensitivity; raw carve
+output has no equivalent encryption.
+
+#### Recommendation
+
+Create sensitive artefacts and parent directories with private modes, tighten
+existing destinations explicitly, and minimise the lifetime of mutable
+plaintext and key buffers. Document that Go strings and internal copies cannot
+be guaranteed to be erased.
+
+#### Safer Example
+
+Implemented:
+
+```go
+f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0600)
+if err == nil {
+    err = f.Chmod(0600)
+}
+```
+
+#### Suggested Tests
+
+POSIX-only regression tests verify `0600` export and carve files and a `0700`
+carve directory, including overwriting a pre-existing `0644` export.
+
+#### References
+
+- CWE-276: Incorrect Default Permissions
+- CWE-316: Cleartext Storage of Sensitive Information in Memory
+
+#### Assumptions / Limitations
+
+POSIX mode bits are not equivalent on Windows, so permission tests skip there.
+`clear` is best-effort in Go and cannot erase immutable password strings,
+copies held by libraries, or compiler-created copies. External extraction
+tools may choose their own modes for files they create beneath the private
+directory.
+
+## 8. Blackhat-Style Abuse Paths
+
+### Path 1: Reconnect churn to process exhaustion
+
+Prerequisite: a profile needs an interactive credential during automatic
+reconnect. A hostile endpoint repeatedly drops the connection. Before the fix,
+each prompt left another Wails listener behind. Defensive breakpoint:
+application-level listener routing, context cancellation, and shutdown
+unsubscribe.
+
+### Path 2: Renderer-driven SFTP handle exhaustion
+
+Prerequisite: renderer access to bound service methods. Start streaming uploads
+without finishing them, then close or reconnect sessions repeatedly. Before the
+fix, writers and upload entries survived. Defensive breakpoint: the 16-upload
+cap and session-owned cancellation.
+
+### Path 3: Passive observation of vulnerable TLS ECH
+
+Prerequisite: affected Go runtime, ECH/PSK behaviour, and network visibility.
+Observe plaintext ClientHello state and correlate exposed PSK identity.
+Defensive breakpoint: Go 1.25.12 or 1.26.5 and later.
+
+### Path 4: Local recovery of carved secrets
+
+Prerequisite: another local account can traverse the selected output location.
+Read a `0644` carved file containing a private key or configuration secret.
+Defensive breakpoint: `0700` directories and `0600` files.
+
+No practical chain to unauthenticated remote code execution was identified.
+
+## 9. Denial-of-Service Review
+
+Fixed in this audit:
+
+- Reconnect secret listeners no longer grow with historical prompt count.
+- Cancelled reconnect prompts stop immediately instead of waiting up to 60
+  seconds.
+- Session close/reconnect and application shutdown drain streaming uploads.
+- Concurrent streaming uploads are capped at 16.
+- Runtime listeners and prompt waiters are released at shutdown.
+- IPv6 literals are joined with ports correctly, preventing connection failure
+  and misleading repeated retry behaviour.
+
+Previously hardened and rechecked:
+
+- SFTP inline/chunk/total upload size caps.
+- VNC WebSocket frame limits.
+- GitHub archive and update-response size limits.
+- SSH configuration and public-key input caps.
+- Recording and Leviathan file-size limits in exposed paths.
+- Session timers, latency pings, frontend intervals, and closed-tab lifecycle
+  cleanup covered by the current regression tests.
+
+Residual considerations:
+
+- Network protocols ultimately depend on remote peer responsiveness.
+- External Leviathan tools lack a shared timeout/output-budget wrapper, but
+  that path is not currently exposed by the active UI API.
+- Hostile binary parsers deserve continued fuzzing even where current bounds
+  checks reject malformed offsets.
+
+## 10. Dependency and Supply-Chain Review
+
+`npm audit --json` reported zero vulnerabilities across 33 frontend
+dependencies.
+
+Post-fix `govulncheck -show verbose` reported:
+
+- Zero vulnerabilities in symbols Nexus calls.
+- Zero vulnerabilities in imported package call paths.
+- Four advisories in required module versions that Nexus does not appear to
+  call:
+  - GO-2026-5970 in `golang.org/x/text@v0.37.0`.
+  - GO-2026-5942 in `golang.org/x/net@v0.55.0`.
+  - GO-2026-5932 for the unmaintained `x/crypto/openpgp` package.
+  - GO-2026-5841 in `github.com/klauspost/compress/s2@v1.17.11`.
+
+Those versions should be refreshed through normal dependency maintenance, but
+they were not forcibly upgraded in this fix because the scanner found no
+Nexus call path and broad transitive churn would require separate compatibility
+testing.
+
+The release workflow uses common GitHub Actions by major version and a
+write-capable release job. Pinning actions to immutable commit SHAs would
+further reduce supply-chain drift. Release permissions should remain scoped to
+the release job and tag/manual triggers.
+
+## 11. Secrets and Sensitive Data Review
+
+No hard-coded production credential, private key, token, or certificate was
+found. Test secrets were confined to test fixtures.
+
+Reviewed controls:
+
+- OS keychain integration.
+- Argon2id-derived AES-GCM vault and export encryption.
+- SSH host-key verification and known-host handling.
+- Bridge bearer token generation and comparison.
+- Secret prompt routing and cancellation.
+- Sensitive file permissions.
+- Logging and frontend error paths for obvious secret disclosure.
+
+Fixed:
+
+- Best-effort clearing of mutable export/import plaintext, password bytes, and
+  derived keys.
+- Private export and carve modes.
+- Prompt waiters and listeners released during shutdown.
+
+Residual:
+
+- Go strings and library copies cannot be reliably zeroed.
+- Users may explicitly choose plaintext Telnet, RAW TCP, or non-TLS VNC.
+- A user can explicitly select insecure SSH host-key behaviour; that choice
+  remains a visible compatibility option and should not be the default.
+
+## 12. Authentication and Authorisation Review
+
+Nexus is a single-user desktop client rather than a multi-tenant server. Its
+primary authorisation boundary is the logged-in OS account plus the Wails
+renderer/backend boundary.
+
+Checked:
+
+- Local bridge endpoints retain bearer-token authentication.
+- SSH host-key callbacks are required in the reviewed direct and tunnel paths.
+- GitHub and remote-session credentials are retrieved from configured secret
+  stores or interactive prompts.
+- Sensitive service methods validate session identifiers through the manager
+  and validate paths, sizes, or option allow-lists where applicable.
+
+No new authentication bypass or cross-user authorisation defect was confirmed.
+A future renderer compromise would still have substantial privileges because
+Wails-bound methods are designed for the trusted desktop UI; maintaining output
+encoding and a narrow method surface therefore remains important.
+
+## 13. Input Validation and Output Encoding Review
+
+Reviewed:
+
+- Profile fields, ports, hostnames, paths, filenames, import strategies,
+  archive/update URLs, SSH key options, recording files, binary offsets, and
+  base64 upload chunks.
+- HTML construction and text insertion in frontend modules.
+- Local subprocess arguments for shell, `ssh-keygen`, and Leviathan extraction.
+
+Fixed:
+
+- `net.JoinHostPort` now constructs IPv4, hostname, and IPv6 endpoints in VNC,
+  IRC SSH tunnels, and the connection tester.
+- Existing SFTP validation is now combined with a concurrency limit and
+  lifecycle cleanup.
+
+Scanner findings for MD5/SHA-1 in Leviathan are intentional forensic hash
+identifiers, not password or signature protection. Representative integer
+conversion and slice warnings in hostile-file parsers were manually traced to
+existing bounds checks; no concrete out-of-bounds path was confirmed. Parser
+fuzzing remains preferable to broad speculative casting changes.
+
+## 14. Frontend HTML/JavaScript Robustness Review
+
+The frontend contains numerous event listeners because each tab and modal owns
+interactive DOM. Reviewed tab/session paths attach handlers to ephemeral nodes
+that become collectable when their owning DOM is removed, while application
+listeners and intervals have explicit one-time or cleanup behaviour.
+
+Current regression coverage verifies session cleanup, active latency timer
+behaviour, closed-tab release, safe DOM patterns, upload constraints, build
+hardening, and other earlier fixes.
+
+The aggregate test harness still referenced VS Code files deleted in
+`4fc3b19` and a CGO flag removed by the same pure-Go migration. This caused
+`npm test` to fail before reaching its current assertions. The stale VS Code
+checks were removed, and the obsolete `-O2 -g0` assertion was replaced with a
+check that the current build retains `CGO_ENABLED=0`. Both frontend suites now
+pass.
+
+No confirmed exploitable current DOM injection was found. Some `innerHTML`
+usage remains and relies on escaping helpers or trusted static markup; future
+changes should prefer `textContent` and DOM construction for dynamic data.
+
+## 15. Infrastructure and Deployment Review
+
+Reviewed:
+
+- Shell, PowerShell, Makefile, and shared build helpers.
+- GitHub Actions release configuration.
+- Updater endpoint and PHP manifest delivery.
+- Cross-platform build flags and Go toolchain selection.
+
+Fixed:
+
+- Unix build scripts now reject Go versions older than 1.25.12.
+- `go.mod` requests Go 1.26.5 while keeping 1.25.12 as the minimum supported
+  language/toolchain floor.
+- Stale regression coverage now reflects the pure-Go build.
+
+The updater remains a high-value trust boundary. Production release validation
+should verify HTTPS, hashes/signatures where supported, expected artefact
+names, and least-privilege release credentials. No new command-injection or
+manifest-escaping defect was confirmed.
+
+## 16. Logging, Monitoring, and Error Handling Review
+
+The new cleanup paths do not log credentials or secret responses. Upload
+cleanup treats remote partial-file deletion as best-effort because the
+underlying session may already be broken.
+
+Useful future operational signals:
+
+- Active and rejected streaming-upload counts.
+- Reconnect attempt count and pending credential prompts.
+- Active runtime listener and session counts in a diagnostics view.
+- Resource snapshots during long-running open/close soak tests.
+
+These should expose counts and identifiers only, never passwords, tokens,
+private keys, terminal contents, or bridge bearer tokens.
+
+## 17. Test Coverage and Security Regression Gaps
+
+Added:
+
+- Credential response routing by request ID.
+- Reconnect cancellation releases its secret prompt immediately.
+- Frontend cancellation is honoured.
+- SFTP cleanup is scoped to the owning session.
+- Active streaming uploads are bounded.
+- Service shutdown releases uploads and prompt waiters.
+- Existing permissive export files are tightened to `0600`.
+- Leviathan carve directories/files use `0700`/`0600`.
+
+Passing:
+
+- Full Go test suite.
+- Focused Go race suite.
+- Go vet.
+- Complete frontend lifecycle and regression suite.
+- Frontend production build.
+- JavaScript, shell, and PHP syntax checks.
+- `npm audit`.
+- Reachable Go vulnerability scan.
+
+Remaining gaps:
+
+- No packaged Wails UI smoke or long-duration tab/reconnect soak test.
+- No real SFTP server test proves partial-file deletion after a broken
+  transport.
+- No live IPv6 protocol endpoint was used.
+- Hostile-file parser coverage is uneven; fuzzing should be expanded.
+- Windows ACL behaviour is not verified by POSIX permission tests.
+- External Leviathan extractors lack integration tests for time and output
+  limits.
+
+## 18. Prioritised Remediation Plan
+
+Immediate:
+
+- Soak-test a packaged app while repeatedly opening, reconnecting, and closing
+  local and remote tabs. Monitor process CPU, memory, goroutines, file
+  descriptors, and listener/upload counts.
+- Exercise interrupted SFTP uploads against a real server and verify local
+  handle cleanup plus remote partial-file behaviour.
+
+Short-term:
+
+- Add a packaged Wails lifecycle smoke test.
+- Add fuzz targets for the highest-complexity Leviathan parsers.
+- Refresh the four module versions with unreachable advisories and run protocol
+  compatibility tests.
+- Add metrics or a diagnostics screen for active sessions, reconnects,
+  uploads, prompts, and event subscriptions.
+
+Medium-term:
+
+- Wrap every external Leviathan extractor with context timeout, process-group
+  termination, and output-size/file-count budgets before exposing extraction
+  through the UI.
+- Replace remaining dynamic `innerHTML` paths with text nodes or narrowly
+  reviewed rendering helpers.
+- Add real IPv6 SSH/VNC/IRC tunnel integration coverage.
+
+Long-term:
+
+- Add release CI gates for full tests, race-focused tests, `govulncheck`,
+  frontend audit/build, packaged smoke checks, and signed artefact validation.
+- Pin third-party GitHub Actions to reviewed immutable revisions.
+
+## 19. False Positives / Needs Manual Verification
+
+- Gosec MD5 and SHA-1 reports in Leviathan are forensic digest features, not
+  security authentication or password hashing.
+- Gosec subprocess reports include user-selected local shells, allow-listed SSH
+  key generation options, and an external extraction path not exposed by the
+  current document API. The extraction path still needs limits before future
+  exposure.
+- File-parser integer-conversion and slice warnings were reviewed
+  representatively; existing range checks rejected the paths inspected.
+  Fuzzing is required for stronger assurance.
+- The four remaining Go module advisories are present in required versions,
+  but `govulncheck` found no called symbol or imported vulnerable package path.
+- The fixed TLS issue had a reachable standard-library path, but actual ECH
+  exposure was not reproduced.
+- Sensitive-buffer clearing is best-effort and must not be described as
+  guaranteed memory erasure in Go.
+
+## 20. Final Notes
+
+The confirmed issues and their regression tests are committed in `b5c7528`.
+The most important improvement for the reported long-running-process behaviour
+is that credential event listeners, prompt waiters, and unfinished upload
+writers now have explicit owners and terminal cleanup paths.
+
+Closing a session now cancels its reconnect work and SFTP uploads; closing all
+sessions drains all uploads; application or bridge shutdown also unregisters
+runtime listeners and releases pending prompts. This materially improves
+cleanup, but live soak testing is still required before claiming that every OS,
+third-party library, and remote-peer resource remains flat indefinitely.

audits/20261012-0723-functionalityNextSteps.md

@@ -0,0 +1,139 @@
+# Functionality and Next Steps Report
+
+**Project:** Nexus Terminal — Rust port (`rust/` workspace)
+**Branch / base commit:** `rust-port` @ `8766846` (after this run: `aac986d`)
+**Date:** 2026-10-12 07:23 (local)
+**Companion:** `audits/20261012-0723-securityAudit.md` (SEC-20261012-NNN references below)
+
+## 1. Executive Summary
+
+The port is functionally complete relative to the Go/Wails app and is in good shape: the core crate is cleanly separated from the UI, every protocol client follows one lifecycle contract (blocking connect, own reader thread, `on_close` exactly once), the test suite (142 tests) exercises real sockets, a real `sshd`, PTYs and fake IRC/VNC/GitHub servers, and `clippy -D warnings` is clean.
+
+The highest-impact improvements now are reliability and user-experience rather than new protocols:
+
+1. **Credential UX** — a mistyped “saved” password is persisted before it is verified and then blocks every reconnect with no re-prompt (SEC-015); store failures are silent.
+2. **Resilience** — a panic on any worker thread poisons shared mutexes and takes the whole app down (`lock().unwrap()` everywhere); there is no panic hook, no crash message and no recovery of open sessions.
+3. **Product/privacy switches** — update checks, remote clipboard writes and multi-line paste all happen without a preference or notice.
+4. **Operability** — recording metadata, audit-log growth and the IRC state model scale poorly with long-running use.
+5. **Developer experience** — fuzz targets, a CI audit step and a documented `cargo clean` note after moving the checkout would have saved time in this run.
+
+## 2. Current Functional Risks
+
+| # | Risk | Where | Effect on users |
+|---|---|---|---|
+| F1 | Saved credential stored before auth succeeds; no path to replace it on failure other than editing the profile | `core/src/sessions.rs` `secret_fn` | Typo → every connect fails silently with the wrong saved password |
+| F2 | `Secrets::set` swallows errors (`let _ =`) | `core/src/secrets.rs` | “Save securely” silently doesn't save when the keychain refuses and the vault is locked |
+| F3 | Mutex poisoning: ~60 `lock().unwrap()` sites; any panic in a callback thread (e.g. a decoder bug) crashes the UI on the next lock | `sessions.rs`, `app.rs`, clients | One bad session kills all sessions, recordings stop mid-write |
+| F4 | No panic hook / crash dialog; `eframe` aborts silently | `app/src/main.rs` | Users see the window vanish with no explanation |
+| F5 | Quick Connect (SSH) allows an empty username; connection then fails at auth with an opaque server error | `app/src/quick_connect.rs`, `service.rs` `connect_quick` (unvalidated) | Confusing failure |
+| F6 | `import_ssh_config` writes profiles without `validate_profile` (e.g. empty `User`) | `core/src/service.rs` | Profiles that fail validation when later edited |
+| F7 | Unknown enum value in a stored JSON column (`hostKeyPolicy`, `lineEnding`, …) makes `parse_col` return `None`; the profile silently reverts that protocol's config to defaults | `core/src/storage.rs` `parse_col` | Lost settings after a downgrade/edit with a newer app |
+| F8 | Empty vault accepts any master password; a typo on first use creates entries under the wrong key (SEC-016) | `core/src/secrets.rs` | Unrecoverable secrets |
+| F9 | Recording listing reads every `.cast` fully (up to 250 MiB each) on the UI's worker thread (SEC-020) | `core/src/recording.rs` `read_meta` | Recordings window stalls with large files |
+| F10 | macOS `capture_cwd` runs `/usr/sbin/lsof` on every Enter in a local shell | `core/src/clients/local.rs` | Noticeable latency on macOS local tabs |
+| F11 | Keychain probe writes and deletes an item at every launch | `core/src/secrets.rs` `Keychain::available` | Keychain prompts/noise on macOS; D-Bus wake-ups on Linux |
+| F12 | Keychain legacy read-through copies `AlchementaryLink` items forward on every miss | `Keychain::get` | Repeated writes for keys that only exist in the legacy service |
+| F13 | GitHub refresh performs up to 5000 commit lookups every refresh interval with 5 threads | `core/src/clients/github.rs` | Token rate-limit exhaustion; 403s surface as “auth failed” |
+| F14 | IRC: channels/users tracked for any JOIN/NAMES seen, UI targets created for any sender (SEC-014) | `irc.rs`, `irc_view.rs` | Memory growth on busy networks |
+| F15 | `check_github` in `updater.rs` is unused (dead code) and hardcodes an owner/repo that may not exist | `core/src/updater.rs` | Misleading; GitHub fallback never runs |
+| F16 | Update check at every launch, no preference, docs say opt-in (SEC-013) | `app/src/app.rs` | Privacy expectation mismatch |
+| F17 | Audit log has no cap/rotation | `storage.rs` `add_audit` | DB grows indefinitely |
+| F18 | Stale `target/` after moving the checkout bakes old `CARGO_MANIFEST_DIR` into fixture tests (4 failures until `cargo clean`) | build hygiene | Confusing CI-vs-local mismatch |
+| F19 | `Secrets::delete_profile` relies on a static list of kinds (`PROFILE_SECRET_KINDS`); the profile editor and session manager still use string literals for kinds | `secrets.rs`, `profile_editor.rs`, `sessions.rs` | A new kind added in one place is missed by the purge |
+| F20 | Reconnect credential prompt timeout is 60 s vs 300 s on first connect | `sessions.rs` `schedule_reconnect` | Reconnects fail if the user is away briefly |
+
+## 3. Code Quality Improvements
+
+- **Secret kinds as a type**: replace the `&'static str` kinds (`"password"`, `"github-token"`, `"vnc-ssh-passphrase"`, …) scattered across `sessions.rs`, `profile_editor.rs` and `secrets.rs` with an enum (`SecretKind`) that has `as_str()` and `ALL`. Why: F19 and SEC-001 depend on the list staying complete. Safe step: enum + `From<&str>`; keep the string form for storage keys.
+- **Poison-tolerant locking**: introduce a small `fn lock<T>(m: &Mutex<T>) -> MutexGuard<T>` that recovers from poisoning (`unwrap_or_else(|e| e.into_inner())`, as `irc.rs`/`vnc.rs` already do) and use it in `sessions.rs`, `ssh.rs`, `app.rs`. Why: F3. Mechanical refactor; existing tests cover behaviour.
+- **Panic hook**: install `std::panic::set_hook` in `main.rs` that logs the payload (no locals) and posts a toast via `post_error`; keep worker panics from killing the UI. Why: F4.
+- **`parse_col` should not swallow errors**: log the parse error and keep the raw JSON (or surface a toast once) instead of returning `None`. Why: F7. Add `#[serde(other)]` variants to the enums so unknown values map to a named `Unknown` instead of failing the whole struct.
+- **`sessions.rs` (1 300 lines)**: split per-protocol connect functions (`connect_ssh/irc/vnc/github`) and the reconnect state machine into modules; the file is the hardest to test in isolation. Behaviour-preserving move; `tests/sessions.rs` guards it.
+- **Thread-per-event**: `on_close` spawns a thread per close and each connect spawns one; fine for a desktop app but makes ordering hard to reason about. Consider one `std::sync::mpsc` worker for lifecycle events.
+- **Duplicated defaults**: `Profile::new`, `Profile::normalize`, `profile_editor::prep` and `SshConfig::defaults` each know the default port/keepalive/retry values. Centralise in `models.rs` constants (already partly done) and have `prep` call `normalize`.
+- **`run_command("pwd")`** is the only use of exec for state; SFTP `realpath(".")` already gives the home — consider dropping the shell call to avoid shells that print banners.
+- **`Keychain::available` probe**: cache the result in preferences with a timestamp; re-probe weekly or on explicit request. Why: F11.
+- **Dead code**: `updater::check_github`, `Protocol::Local` branches in validation (`unsupported protocol`). Remove or wire up.
+- **`Store::migrate`**: wrap each migration in a transaction and record `schema_version` explicitly in code rather than relying on the SQL files to insert it (verify each file does).
+
+## 4. Frontend Interaction and Error-Handling Improvements
+
+The UI is native egui; the equivalent of “event firing / async failures / console diagnostics” was reviewed:
+
+- **Async failures surface**: every worker reports through `Job`, `Inbox`, `post_error` or `Shared::spawn`; the pattern is consistent. Gap: `Secrets::set` (F2) and `let _ = self.store.update_profile(&p)` in `connect_profile` discard errors — toast them.
+- **Modal keyboard handling**: `prompts()` and `dialogs()` read `Key::Enter`/`Escape` globally; with two modals stacked (a credential prompt while the Delete dialog is open) one key can act on both. Route keys only to the top-most modal (check `app.prompts.is_empty()` before dialogs read Enter).
+- **Credential prompt**: show which credential kind and profile; add “Save this credential” checkbox when the profile is in ask-every-time mode; after an auth failure with a saved secret, offer “Re-enter”.
+- **Host-key prompt**: offer “Copy fingerprint” and show the port; on key change, show both fingerprints side by side with a “Remove old key” action (today the user must go to Settings → Known Hosts).
+- **Clipboard from remote** (SEC-010): toast with the first line whenever OSC 52 or VNC sets the clipboard; preference to disable.
+- **Multi-line paste** (SEC-017): confirmation preview when the terminal is not in bracketed-paste mode.
+- **Transfers**: SFTP upload stops at the first failure and drops the rest of the queue (by design) — show which files were skipped.
+- **Console diagnostics**: adopt `tracing` with `RUST_LOG` support for connection lifecycle (host, protocol, state, error) — never credentials, never terminal data; today only `eprintln!` for CLI misuse exists.
+- **Crash fallback** (F4): panic hook + “Nexus Terminal hit an internal error; sessions were kept open where possible” dialog.
+- **Screenshot automation flags** (`--answer`): read from `NEXUS_ANSWERS` env/file instead of argv (SEC-018) and print a warning when used without `--screenshot`.
+
+## 5. Testing Roadmap
+
+- **Unit**: `secret_fn` ordering (store after success), `Vault` verifier (once added), `parse_col` unknown-enum behaviour, IRC state caps, `read_meta` tail parsing, `export_json` redaction of login-script sends.
+- **Integration**: extend `tests/ssh_integration.rs` with password + keyboard-interactive auth (sshd with `PasswordAuthentication yes` and a PAM-less test user is awkward; alternatively a russh server fixture), host-key change detection against the known-hosts table, remote forward teardown, SFTP rename/mkdir/remove.
+- **Abuse-case / fuzz**: `cargo-fuzz` targets for `vnc::read_update` (+ decoders), `telnet::Inner::process`, `irc::parse_line` + `ircformat::format_event`, `recording::Store::get`, `sshconfig::parse`, `updater::parse_manifest`. Run in CI nightly with a corpus from the existing fake-server tests.
+- **UI interaction**: the `--screenshot --do --answer` automation already drives the app headlessly; turn it into a smoke test matrix in CI (connect to the in-test sshd, open SFTP, run a palette command, assert the PNG is non-empty and the process exits 0).
+- **Regression**: keep the Go-fixture compatibility tests; add a fixture written by *this* version so future format changes are caught both ways.
+- **Load**: the ignored `perf::feed_throughput` test (50 MiB through the VT parser) should run in release mode in CI with a threshold; add a VNC decode benchmark on a synthetic 4K frame.
+- **Smoke**: `cargo audit` and `cargo deny check licenses advisories` jobs; `cargo test --locked` already runs on three OSes.
+
+## 6. Recommended New Functionality
+
+- **Preferences**: check-for-updates on/off (SEC-013), allow remote clipboard writes (SEC-010), confirm multi-line paste (SEC-017), confirm before `insecure` host-key policy connects.
+- **Credential management**: a Settings → Credentials page listing stored kinds per profile with “forget” buttons; master-password change (re-encrypt vault); export/import of the vault.
+- **Known hosts**: import from `~/.ssh/known_hosts` and export to it; SSH certificate CA trust (`@cert-authority`) since russh already parses certificates.
+- **Update integrity**: signed manifest (minisign/Ed25519), verified before display; optional in-app download with sha256 + signature check.
+- **IRC**: SASL PLAIN/EXTERNAL (modern networks reject NickServ IDENTIFY over plaintext), IRCv3 message tags for timestamps, per-network ISUPPORT line length.
+- **Serial**: session logging to file, hex view like RAW, break duration setting.
+- **SFTP**: recursive directory upload/download, drag-out to the desktop, resume on reconnect.
+- **Session**: “Send to all tabs in group”, per-session environment overrides for local shells, custom shell arguments.
+- **Operability**: audit-log viewer with cap/rotation; recordings metadata cache; “Diagnostics” page (keychain status, data dir, versions of russh/rustls, last update check).
+
+## 7. Next-Level Opportunities
+
+- **Observability**: `tracing` + optional file log with redaction; connection timing metrics in the status bar; opt-in crash reports (local file only).
+- **Resilience architecture**: supervisor-style session threads that catch panics per session (`std::panic::catch_unwind` around client callbacks) so one protocol bug cannot end the app.
+- **Security architecture**: move all secret-bearing fields out of `Profile` into the secret store behind a migration (keeps `.nexus` compatibility by exporting them inline only when “include secrets” is chosen); `Zeroizing`/`SecretString` throughout; Linux `PR_SET_DUMPABLE` while the vault is unlocked.
+- **Distribution**: signed, notarised builds; Flatpak/AppImage with sandboxing (`--filesystem=home:ro` + explicit `~/.ssh`), winget/Homebrew casks; SLSA provenance from the release workflow.
+- **Performance**: VNC — upload only dirty rows to the texture (`TextureHandle::set_partial`), decode JPEG on the I/O thread (already) but avoid the full `local.clone()` on resize; terminal — batch paint runs per style (already) and cache galleys per row.
+- **Accessibility**: egui `accesskit` is enabled; audit focus order in modals and provide screen-reader labels for icon-only buttons (`widgets::icon_button` has hover text only).
+- **Developer experience**: `justfile`/`make` targets for `test`, `clippy`, `audit`, `screenshot-smoke`; a `CONTRIBUTING.md` note about `cargo clean` after moving the checkout (F18); fuzz corpus checked in.
+
+## 8. Prioritised Action Plan
+
+**Immediate (this week)** — low risk, high value
+- Add the three preferences (update check, remote clipboard, paste confirmation) with safe defaults. Risk: trivial.
+- Toast on `Secrets::set` failure; store saved credentials after auth success (F1/F2). Risk: touches the auth path; covered by sshd tests — add a keyboard-interactive case.
+- Poison-tolerant lock helper + panic hook (F3/F4). Risk: mechanical.
+- Add `cargo audit` to CI with SEC-012 ignored and dated (outside `rust/`, owner's call).
+
+**Short term (next release)**
+- IRC state caps and joined-only tracking (F14).
+- `parse_col` error visibility and `Unknown` enum variants (F7).
+- Vault verifier entry (F8); keychain probe caching (F11).
+- Known-hosts import/export; host-key change dialog improvements.
+- Recording metadata from file tail (F9).
+
+**Medium term**
+- Secret-kind enum and credential management page (F19).
+- Fuzz targets + nightly job; screenshot smoke matrix.
+- Signed update manifest; release signing.
+- SASL for IRC; SFTP recursive transfers.
+
+**Long term**
+- Move profile-embedded secrets into the store with migration; `SecretString` everywhere.
+- Per-session panic isolation; `tracing`-based diagnostics.
+- Sandboxed distribution and provenance.
+
+## 9. Caveats and Validation Needed
+
+- Keychain behaviour (purge on delete, probe cost, legacy copy-forward) was verified by reading `keyring` usage, not by running against macOS Keychain, Windows Credential Manager or a live Secret Service; test on each OS before release.
+- The in-process key generator (`ssh::generate_key_pair`) was tested for Ed25519 and ECDSA; RSA generation runs the `rsa` crate's keygen (slow in debug builds — verify the UI stays responsive and that OpenSSH accepts the files on all three platforms).
+- `--data-dir` now creates directories 0700; if any user relies on sharing a portable data directory between accounts this changes behaviour.
+- The VNC size cap (64 Mpx) is above any real display; confirm with multi-monitor spanning setups (e.g. 3×4K = 37 Mpx) before lowering it.
+- Preference defaults for update checks and remote clipboard are product decisions; both have compatibility implications (vim/tmux yank over SSH relies on OSC 52).
+- UI event flows were validated by code review and the existing automation flags, not by an interactive run in this environment.

build-all.sh

@@ -1,170 +0,0 @@
-#!/usr/bin/env bash
-# build-all.sh — Cross-build helper for Nexus Terminal (macOS/Linux hosts)
-# Builds all supported targets where the required toolchains are installed.
-# Usage: ./build-all.sh
-set -euo pipefail
-
-SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-cd "$SCRIPT_DIR"
-
-GREEN='\033[0;32m'
-YELLOW='\033[1;33m'
-RED='\033[0;31m'
-NC='\033[0m'
-
-log()  { echo -e "${GREEN}[nexus]${NC} $1"; }
-warn() { echo -e "${YELLOW}[nexus]${NC} $1"; }
-err()  { echo -e "${RED}[nexus]${NC} $1" >&2; }
-
-build_tags() {
-    if command -v pkg-config >/dev/null 2>&1 \
-        && pkg-config --exists webkit2gtk-4.1 \
-        && ! pkg-config --exists webkit2gtk-4.0; then
-        echo "webkit2_41"
-    fi
-}
-
-build_version() {
-    local tag
-    local commit
-    tag="$(git describe --tags --abbrev=0 2>/dev/null || echo "dev")"
-    commit="$(git rev-parse --short HEAD 2>/dev/null || echo "unknown")"
-    echo "${tag}-${commit}"
-}
-
-build_ldflags() {
-    local version="$1"
-    local flags="-s -w -X github.com/andydixon/nexus/internal/api.appVersion=${version}"
-    if [ -n "${NEXUS_UPDATE_URL:-}" ]; then
-        flags="${flags} -X github.com/andydixon/nexus/internal/api.appUpdateURL=${NEXUS_UPDATE_URL}"
-    fi
-    echo "${flags}"
-}
-
-check_deps() {
-    command -v go >/dev/null 2>&1 || { err "Go is not installed"; exit 1; }
-    command -v node >/dev/null 2>&1 || { err "Node.js is not installed"; exit 1; }
-    command -v npm >/dev/null 2>&1 || { err "npm is not installed"; exit 1; }
-
-    if ! command -v wails >/dev/null 2>&1; then
-        if [ -f "$HOME/go/bin/wails" ]; then
-            export PATH="$PATH:$HOME/go/bin"
-        else
-            err "Wails is not installed. Run: go install github.com/wailsapp/wails/v2/cmd/wails@latest"
-            exit 1
-        fi
-    fi
-
-    log "Go:    $(go version)"
-    log "Node:  $(node --version)"
-    log "Wails: $(wails version 2>/dev/null | head -1)"
-}
-
-install_deps() {
-    log "Installing Go dependencies…"
-    go mod download
-
-    log "Installing frontend dependencies…"
-    cd frontend && npm install && cd ..
-}
-
-host_os() {
-    case "$(uname -s)" in
-        Darwin) echo "darwin" ;;
-        Linux) echo "linux" ;;
-        *) echo "unknown" ;;
-    esac
-}
-
-pick_cc() {
-    local target_os="$1"
-    local target_arch="$2"
-
-    if [ "$target_os" = "windows" ]; then
-        if [ "$target_arch" = "amd64" ]; then
-            echo "x86_64-w64-mingw32-gcc"
-        else
-            echo "aarch64-w64-mingw32-gcc"
-        fi
-        return
-    fi
-
-    if [ "$target_os" = "linux" ]; then
-        if [ "$target_arch" = "amd64" ]; then
-            echo "x86_64-linux-gnu-gcc"
-        else
-            echo "aarch64-linux-gnu-gcc"
-        fi
-        return
-    fi
-
-    echo ""
-}
-
-build_target() {
-    local target_os="$1"
-    local target_arch="$2"
-    local host="$3"
-    local version="$4"
-    local ldflags
-    ldflags="$(build_ldflags "${version}")"
-    local tags
-    tags="$(build_tags)"
-
-    local platform="${target_os}/${target_arch}"
-    local cc=""
-
-    if [ "$target_os" != "$host" ]; then
-        cc="$(pick_cc "$target_os" "$target_arch")"
-        if [ -n "$cc" ] && ! command -v "$cc" >/dev/null 2>&1; then
-            warn "Skipping ${platform} (missing C compiler: ${cc})"
-            return 0
-        fi
-    fi
-
-    log "Building ${platform}…"
-    if [ -n "$cc" ]; then
-        if [ -n "$tags" ]; then
-            CC="$cc" CGO_ENABLED=1 wails build -platform "$platform" -tags "$tags" -ldflags "$ldflags"
-        else
-            CC="$cc" CGO_ENABLED=1 wails build -platform "$platform" -ldflags "$ldflags"
-        fi
-    else
-        if [ -n "$tags" ]; then
-            CGO_ENABLED=1 wails build -platform "$platform" -tags "$tags" -ldflags "$ldflags"
-        else
-            CGO_ENABLED=1 wails build -platform "$platform" -ldflags "$ldflags"
-        fi
-    fi
-}
-
-main() {
-    check_deps
-    install_deps
-
-    local version
-    version="$(build_version)"
-
-    local host
-    host="$(host_os)"
-    if [ "$host" = "unknown" ]; then
-        err "Unsupported host OS for this script. Use macOS or Linux."
-        exit 1
-    fi
-
-    # Build host targets first
-    build_target "$host" "amd64" "$host" "$version"
-    build_target "$host" "arm64" "$host" "$version"
-
-    # Cross-build Linux and Windows targets where toolchains are available
-    if [ "$host" = "darwin" ] || [ "$host" = "linux" ]; then
-        build_target "linux" "amd64" "$host" "$version"
-        build_target "linux" "arm64" "$host" "$version"
-        build_target "windows" "amd64" "$host" "$version"
-        build_target "windows" "arm64" "$host" "$version"
-    fi
-
-    log "Builds complete. Output: build/bin/"
-}
-
-main "$@"

build.ps1

@@ -1,124 +0,0 @@
-# build.ps1 — Windows build script for Nexus Terminal
-# Usage: .\build.ps1 [dev|build|test|clean|deps]
-Set-StrictMode -Version Latest
-$ErrorActionPreference = 'Stop'
-
-function Write-Info($Message) { Write-Host "[nexus] $Message" -ForegroundColor Green }
-function Write-Warn($Message) { Write-Host "[nexus] $Message" -ForegroundColor Yellow }
-function Write-Err($Message)  { Write-Host "[nexus] $Message" -ForegroundColor Red }
-
-function Get-WailsPath {
-    $wails = Get-Command wails -ErrorAction SilentlyContinue
-    if ($wails) { return $wails.Source }
-
-    $goPath = & go env GOPATH
-    $fallback = Join-Path $goPath 'bin\wails.exe'
-    if (Test-Path $fallback) { return $fallback }
-    return $null
-}
-
-function Check-Deps {
-    if (-not (Get-Command go -ErrorAction SilentlyContinue)) { throw 'Go is not installed.' }
-    if (-not (Get-Command node -ErrorAction SilentlyContinue)) { throw 'Node.js is not installed.' }
-    if (-not (Get-Command npm -ErrorAction SilentlyContinue)) { throw 'npm is not installed.' }
-
-    $wailsPath = Get-WailsPath
-    if (-not $wailsPath) {
-        throw 'Wails is not installed. Run: go install github.com/wailsapp/wails/v2/cmd/wails@latest'
-    }
-
-    Write-Info "Go:    $(& go version)"
-    Write-Info "Node:  $(& node --version)"
-    Write-Info "Wails: $(& $wailsPath version | Select-Object -First 1)"
-
-    if (-not (Get-Command gcc -ErrorAction SilentlyContinue)) {
-        Write-Warn 'gcc not found. SQLite requires cgo + a C compiler (e.g. MSYS2 mingw-w64).'
-    }
-
-    return $wailsPath
-}
-
-function Install-Deps {
-    Write-Info 'Installing Go dependencies...'
-    & go mod download
-
-    Write-Info 'Installing frontend dependencies...'
-    Push-Location 'frontend'
-    & npm install
-    Pop-Location
-}
-
-function Get-BuildVersion {
-    try {
-        $tag = & git describe --tags --abbrev=0 2>$null
-        if (-not $tag) { $tag = 'dev' }
-    } catch {
-        $tag = 'dev'
-    }
-
-    try {
-        $commit = & git rev-parse --short HEAD 2>$null
-        if (-not $commit) { $commit = 'unknown' }
-    } catch {
-        $commit = 'unknown'
-    }
-
-    return "$tag-$commit"
-}
-
-function Get-Ldflags([string]$Version) {
-    $flags = "-s -w -X github.com/andydixon/nexus/internal/api.appVersion=$Version"
-    if ($env:NEXUS_UPDATE_URL) {
-        $flags += " -X github.com/andydixon/nexus/internal/api.appUpdateURL=$($env:NEXUS_UPDATE_URL)"
-    }
-    return $flags
-}
-
-function Dev {
-    $wailsPath = Check-Deps
-    Install-Deps
-    Write-Info 'Starting development mode...'
-    & $wailsPath dev
-}
-
-function Build {
-    $wailsPath = Check-Deps
-    Install-Deps
-    $version = Get-BuildVersion
-    $ldflags = Get-Ldflags $version
-
-    $env:CGO_ENABLED = '1'
-    Write-Info 'Building production binary (CGO_ENABLED=1)...'
-    & $wailsPath build -ldflags $ldflags
-    Write-Info 'Build complete: build\bin\'
-}
-
-function Run-Tests {
-    Write-Info 'Running tests...'
-    & go test ./... -v -count=1
-}
-
-function Clean {
-    Write-Info 'Cleaning build artefacts...'
-    Remove-Item -Recurse -Force -ErrorAction SilentlyContinue build\bin
-    Remove-Item -Recurse -Force -ErrorAction SilentlyContinue frontend\node_modules
-    Remove-Item -Recurse -Force -ErrorAction SilentlyContinue frontend\src\js\lib
-    Remove-Item -Recurse -Force -ErrorAction SilentlyContinue frontend\src\css\lib
-    & go clean -testcache
-    Write-Info 'Clean complete'
-}
-
-$task = $args[0]
-if (-not $task) { $task = 'build' }
-
-switch ($task) {
-    'dev'   { Dev }
-    'build' { Build }
-    'test'  { Run-Tests }
-    'clean' { Clean }
-    'deps'  { Check-Deps | Out-Null; Install-Deps }
-    default {
-        Write-Err 'Usage: .\\build.ps1 [dev|build|test|clean|deps]'
-        exit 1
-    }
-}

build.sh

@@ -1,131 +0,0 @@
-#!/usr/bin/env bash
-# build.sh — Build script for Nexus Terminal
-# Provides a reproducible build process for CI and local builds.
-# Usage: ./build.sh [dev|build|test|clean|deps]
-set -euo pipefail
-
-SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-cd "$SCRIPT_DIR"
-
-# Colours for output
-RED='\033[0;31m'
-GREEN='\033[0;32m'
-YELLOW='\033[1;33m'
-NC='\033[0m'
-
-log()  { echo -e "${GREEN}[nexus]${NC} $1"; }
-warn() { echo -e "${YELLOW}[nexus]${NC} $1"; }
-err()  { echo -e "${RED}[nexus]${NC} $1" >&2; }
-
-build_tags() {
-    if command -v pkg-config >/dev/null 2>&1 \
-        && pkg-config --exists webkit2gtk-4.1 \
-        && ! pkg-config --exists webkit2gtk-4.0; then
-        echo "webkit2_41"
-    fi
-}
-
-build_version() {
-    local tag
-    local commit
-    tag="$(git describe --tags --abbrev=0 2>/dev/null || echo "dev")"
-    commit="$(git rev-parse --short HEAD 2>/dev/null || echo "unknown")"
-    echo "${tag}-${commit}"
-}
-
-build_ldflags() {
-    local version="$1"
-    local flags="-s -w -X github.com/andydixon/nexus/internal/api.appVersion=${version}"
-    if [ -n "${NEXUS_UPDATE_URL:-}" ]; then
-        flags="${flags} -X github.com/andydixon/nexus/internal/api.appUpdateURL=${NEXUS_UPDATE_URL}"
-    fi
-    echo "${flags}"
-}
-
-# Check prerequisites
-check_deps() {
-    command -v go >/dev/null 2>&1 || { err "Go is not installed"; exit 1; }
-    command -v node >/dev/null 2>&1 || { err "Node.js is not installed"; exit 1; }
-    command -v npm >/dev/null 2>&1 || { err "npm is not installed"; exit 1; }
-
-    if ! command -v wails >/dev/null 2>&1; then
-        if [ -f "$HOME/go/bin/wails" ]; then
-            export PATH="$PATH:$HOME/go/bin"
-        else
-            err "Wails is not installed. Run: go install github.com/wailsapp/wails/v2/cmd/wails@latest"
-            exit 1
-        fi
-    fi
-
-    log "All prerequisites found"
-    log "Go:    $(go version)"
-    log "Node:  $(node --version)"
-    log "Wails: $(wails version 2>/dev/null | head -1)"
-}
-
-# Install dependencies
-install_deps() {
-    log "Installing Go dependencies…"
-    go mod download
-
-    log "Installing frontend dependencies…"
-    cd frontend && npm install && cd ..
-
-    log "Dependencies installed"
-}
-
-# Development mode
-dev() {
-    check_deps
-    install_deps
-    log "Starting development mode…"
-    wails dev
-}
-
-# Production build
-build() {
-    check_deps
-    install_deps
-    log "Building production binary…"
-    local version
-    version="$(build_version)"
-    local tags
-    tags="$(build_tags)"
-    if [ -n "$tags" ]; then
-        log "Using Wails build tags: ${tags}"
-        wails build -tags "$tags" -ldflags "$(build_ldflags "${version}")"
-    else
-        wails build -ldflags "$(build_ldflags "${version}")"
-    fi
-    log "Build complete: build/bin/"
-}
-
-# Run tests
-run_tests() {
-    log "Running tests…"
-    go test ./... -v -count=1
-}
-
-# Clean build artefacts
-clean() {
-    log "Cleaning build artefacts…"
-    rm -rf build/bin
-    rm -rf frontend/node_modules
-    rm -rf frontend/src/js/lib
-    rm -rf frontend/src/css/lib
-    go clean -testcache
-    log "Clean complete"
-}
-
-# Main
-case "${1:-build}" in
-    dev)     dev ;;
-    build)   build ;;
-    test)    run_tests ;;
-    clean)   clean ;;
-    deps)    check_deps && install_deps ;;
-    *)
-        echo "Usage: $0 [dev|build|test|clean|deps]"
-        exit 1
-        ;;
-esac

build/darwin/Info.plist

@@ -1,69 +0,0 @@
-<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-<plist version="1.0">
-    <dict>
-        <key>CFBundlePackageType</key>
-        <string>APPL</string>
-        <key>CFBundleName</key>
-        <string>{{.Info.ProductName}}</string>
-        <key>CFBundleExecutable</key>
-        <string>{{.OutputFilename}}</string>
-        <key>CFBundleIdentifier</key>
-        <string>com.andydixon.nexusterminal</string>
-        <key>CFBundleVersion</key>
-        <string>{{.Info.ProductVersion}}</string>
-        <key>CFBundleGetInfoString</key>
-        <string>{{.Info.Comments}}</string>
-        <key>CFBundleShortVersionString</key>
-        <string>{{.Info.ProductVersion}}</string>
-        <key>CFBundleIconFile</key>
-        <string>iconfile</string>
-        <key>LSMinimumSystemVersion</key>
-        <string>10.13.0</string>
-        <key>LSApplicationCategoryType</key>
-        <string>public.app-category.developer-tools</string>
-        <key>NSHighResolutionCapable</key>
-        <string>true</string>
-        <key>NSSupportsAutomaticTermination</key>
-        <false/>
-        <key>NSSupportsSuddenTermination</key>
-        <false/>
-        <key>NSHumanReadableCopyright</key>
-        <string>{{.Info.Copyright}}</string>
-        {{if .Info.FileAssociations}}
-        <key>CFBundleDocumentTypes</key>
-        <array>
-          {{range .Info.FileAssociations}}
-          <dict>
-            <key>CFBundleTypeExtensions</key>
-            <array>
-              <string>{{.Ext}}</string>
-            </array>
-            <key>CFBundleTypeName</key>
-            <string>{{.Name}}</string>
-            <key>CFBundleTypeRole</key>
-            <string>{{.Role}}</string>
-            <key>CFBundleTypeIconFile</key>
-            <string>{{.IconName}}</string>
-          </dict>
-          {{end}}
-        </array>
-        {{end}}
-        {{if .Info.Protocols}}
-        <key>CFBundleURLTypes</key>
-        <array>
-          {{range .Info.Protocols}}
-            <dict>
-                <key>CFBundleURLName</key>
-                <string>com.wails.{{.Scheme}}</string>
-                <key>CFBundleURLSchemes</key>
-                <array>
-                    <string>{{.Scheme}}</string>
-                </array>
-                <key>CFBundleTypeRole</key>
-                <string>{{.Role}}</string>
-            </dict>
-          {{end}}
-        </array>
-        {{end}}
-    </dict>
-</plist>

build/windows/info.json

@@ -1,15 +0,0 @@
-{
-	"fixed": {
-		"file_version": "{{.Info.ProductVersion}}"
-	},
-	"info": {
-		"0000": {
-			"ProductVersion": "{{.Info.ProductVersion}}",
-			"CompanyName": "{{.Info.CompanyName}}",
-			"FileDescription": "{{.Info.ProductName}}",
-			"LegalCopyright": "{{.Info.Copyright}}",
-			"ProductName": "{{.Info.ProductName}}",
-			"Comments": "{{.Info.Comments}}"
-		}
-	}
-}

build/windows/wails.exe.manifest

@@ -1,15 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
-<assembly manifestVersion="1.0" xmlns="urn:schemas-microsoft-com:asm.v1" xmlns:asmv3="urn:schemas-microsoft-com:asm.v3">
-    <assemblyIdentity type="win32" name="com.wails.{{.Name}}" version="{{.Info.ProductVersion}}.0" processorArchitecture="*"/>
-    <dependency>
-        <dependentAssembly>
-            <assemblyIdentity type="win32" name="Microsoft.Windows.Common-Controls" version="6.0.0.0" processorArchitecture="*" publicKeyToken="6595b64144ccf1df" language="*"/>
-        </dependentAssembly>
-    </dependency>
-    <asmv3:application>
-        <asmv3:windowsSettings>
-            <dpiAware xmlns="http://schemas.microsoft.com/SMI/2005/WindowsSettings">true/pm</dpiAware> <!-- fallback for Windows 7 and 8 -->
-            <dpiAwareness xmlns="http://schemas.microsoft.com/SMI/2016/WindowsSettings">permonitorv2,permonitor</dpiAwareness> <!-- falls back to per-monitor if per-monitor v2 is not supported -->
-        </asmv3:windowsSettings>
-    </asmv3:application>
-</assembly>

docs/build-and-release.md

@@ -1,77 +1,74 @@
 # Build and Release
 
-This project uses [Wails](https://wails.io/) for desktop packaging.
+Nexus Terminal is a Rust workspace in `rust/`:
 
-## Ubuntu 24.04 prerequisites
-
-Install the Linux build toolchain and Wails runtime headers with:
-
-```bash
-sudo apt-get update
-sudo apt-get install -y \
-  build-essential \
-  libgtk-3-dev \
-  libwebkit2gtk-4.1-dev \
-  libayatana-appindicator3-dev \
-  pkg-config \
-  zip
+```
+rust/
+├── core/   nexus-core: storage, secrets, protocol clients, session manager, Service. No GUI.
+└── app/    nexus: the egui desktop app (binary `nexus-terminal`)
 ```
 
-Notes:
+The toolchain is pinned in `rust/rust-toolchain.toml`; `rustup` installs it on first build.
 
-- Ubuntu 24.04 does not ship `libwebkit2gtk-4.0-dev`.
-- Wails `v2.12.0` supports Ubuntu 24.04 by building with the `webkit2_41` tag.
-- The local build scripts detect that package layout automatically and add the tag when needed.
+## Prerequisites
 
-You will also need these tools available in `PATH`:
+- **All platforms:** [rustup](https://rustup.rs).
+- **Linux:** the X11/Wayland/GL headers eframe links against, and GTK for native file dialogs:
 
-- `go`
-- `node`
-- `npm`
-- `wails`
+  ```bash
+  sudo apt-get install -y build-essential pkg-config libxkbcommon-dev libgl1-mesa-dev \
+    libx11-dev libxcursor-dev libxrandr-dev libxi-dev libwayland-dev libgtk-3-dev libasound2-dev zip
+  ```
 
-Install the Wails CLI with:
+- **macOS:** Xcode command-line tools (`xcode-select --install`).
+- **Windows:** the MSVC build tools (Visual Studio Build Tools, "Desktop development with C++").
+
+There are no runtime C libraries to install: SQLite is compiled in and TLS uses rustls.
+
+## Build and run
 
 ```bash
-go install github.com/wailsapp/wails/v2/cmd/wails@latest
-export PATH="$PATH:$(go env GOPATH)/bin"
+cd rust
+cargo run --release                 # the app
+cargo test --workspace              # unit and integration tests
+cargo clippy --workspace -- -D warnings
 ```
 
-## Build commands
+Useful flags (also handy for testing): `nexus-terminal [--theme pro|midnight|light]
+[--data-dir DIR] [--screenshot out.png] [--size WxH] [--run-local CMD]`. `--data-dir` points at
+another data directory; `--screenshot` renders the window, saves a PNG and exits (works under
+`xvfb-run`); `--run-local` opens a local terminal and types `CMD` into it.
 
-Build the app binary for the current host:
-
-```bash
-./build.sh
-```
-
-Build a packaged release for the current host platform:
-
-```bash
-./release.sh
-```
-
-By default, `./release.sh` now builds only the current host OS/architecture. On this Ubuntu 24.04 `amd64` host that means `linux/amd64`.
-
-## Optional cross-compilers
-
-If you want to add extra Linux/Windows targets from Ubuntu, install the relevant cross-compiler packages first:
-
-```bash
-sudo apt-get install -y \
-  gcc-aarch64-linux-gnu \
-  gcc-mingw-w64-x86-64
-```
-
-Then request explicit targets:
+The SSH integration tests start a throwaway `sshd` as the current user on a random port; they
+skip themselves when OpenSSH isn't installed.
+
+## Release packages
 
 ```bash
+cd rust
+./release.sh                                            # this machine's platform
 NEXUS_RELEASE_TARGETS=linux/amd64,windows/amd64 ./release.sh
 ```
 
-## Platform caveats
+Artefacts land in `build/releases/<version>/` at the repo root:
 
-- macOS targets cannot be cross-built from Linux with Wails. Build those on macOS.
-- `windows/arm64` is not covered by the default Ubuntu toolchain here.
-- `linux/arm64` needs more than `gcc-aarch64-linux-gnu`; it also needs an `arm64` sysroot and target GTK/WebKit development libraries for CGO to link cleanly.
-- Tested on Ubuntu 24.04 `amd64`: `linux/amd64` and `windows/amd64` build successfully; `linux/arm64` does not in the default host setup above.
+- `NexusTerminal-<os>-<arch>.zip` — on macOS a universal-capable `.app` bundle
+  (`rust/packaging/macos/build-app.sh`), on Windows the `.exe` (icon and version info embedded,
+  GUI subsystem), on Linux the binary plus `install.sh` and a `.desktop` entry
+  (`rust/packaging/linux/install.sh` installs into `~/.local`).
+- `manifest-<os>-<arch>.json` and `version-<os>-<arch>.txt` for the update server
+  (`updates/index.php`), in the same format as before.
+
+The version is `<latest tag>-<short commit>` unless `NEXUS_VERSION` is set. The update manifest
+URL is compiled in from `NEXUS_UPDATE_URL` (default in `release.sh`); `{platform}` and `{arch}` use
+the old Go names (`darwin`/`linux`/`windows`, `amd64`/`arm64`).
+
+Cross-building `windows/amd64` from Linux works with `x86_64-pc-windows-gnu` and mingw-w64.
+macOS bundles must be built on a Mac. CI (`.github/workflows/release-builds.yml`) builds every
+platform natively on GitHub runners and attaches the zips to tagged releases;
+`.github/workflows/ci.yml` runs tests and clippy on Linux, macOS and Windows.
+
+## Signing
+
+macOS bundles are ad-hoc signed. For distribution, sign with a Developer ID and notarize (see the
+comments in `build-app.sh`). Windows binaries are unsigned.

docs/guide/Makefile

@@ -0,0 +1,11 @@
+# Builds nexus-guide.pdf with LuaLaTeX (three passes: contents, page references, then page overlays settle).
+# Needs LuaLaTeX with luaotfload (Debian/Ubuntu: texlive-luatex texlive-latex-extra).
+# Screenshots: tools/screenshots.sh (needs xvfb-run, sshd, python3).
+OUT ?= build
+nexus-guide.pdf: nexus-guide.tex nexus-guide.sty chapters/*.tex img/*
+	mkdir -p $(OUT)
+	lualatex -interaction=nonstopmode -halt-on-error -output-directory=$(OUT) nexus-guide.tex > /dev/null || (grep -A8 '^!' $(OUT)/nexus-guide.log; false)
+	for i in 1 2; do lualatex -interaction=nonstopmode -halt-on-error -output-directory=$(OUT) nexus-guide.tex > /dev/null; done
+	cp $(OUT)/nexus-guide.pdf .
+clean:
+	rm -rf $(OUT)

docs/guide/chapters/appendix.tex

@@ -0,0 +1,120 @@
+\guidepart{slate}{Extras}{The extras}
+  {The cheat sheet, the command line, and words you might trip over.}
+  {\partitem{\iKeyboard}{Keyboard cheat sheet}
+   \partitem{\iTerminal}{Command-line options}
+   \partitem{\iBrain}{Glossary}}
+
+% =========================================================================================
+\chapter{Keyboard cheat sheet}\label{app:keys}
+\chapmeta{print it}{Stick this page next to your monitor}
+
+\newcommand\shortcut[2]{#1 & #2\\}
+\newcommand\sheet[3]{%
+  \begin{tcolorbox}[enhanced, arc=8pt, boxrule=0pt, colback=#1!7, left=10pt, right=10pt, top=8pt, bottom=8pt,
+    before skip=0pt, after skip=10pt, fontupper=\small]
+  {\heavy\large\color{#1!85!black}#2}\par\vspace{4pt}
+  \renewcommand\arraystretch{1.5}\begin{tabularx}{\linewidth}{@{}X>{\raggedleft\arraybackslash}p{36mm}@{}}#3\end{tabularx}
+  \end{tcolorbox}}
+
+\begin{multicols}{2}
+\sheet{accent}{\iRocket\enspace Everywhere}{%
+  \shortcut{Command palette}{\keys{\mod+K}}
+  \shortcut{New connection}{\keys{\mod+N}}
+  \shortcut{Quick Connect}{\keys{\mod+Shift+Q}}
+  \shortcut{Settings}{\keys{\mod+,}}
+  \shortcut{Full screen}{\kbd{F11}}}
+
+\sheet{violet}{\iSplit\enspace Tabs \& panes}{%
+  \shortcut{Close tab}{\keys{\mod+W}}
+  \shortcut{Next tab}{\keys{\mod+Tab}}
+  \shortcut{Previous tab}{\keys{\mod+Shift+Tab}}
+  \shortcut{Go to tab 1–9}{\keys{\mod+1}…\kbd{9}}
+  \shortcut{Split right}{\keys{\mod+Shift+D}}
+  \shortcut{Split down}{\keys{\mod+Shift+E}}}
+
+\sheet{teal}{\iWand\enspace Power tools}{%
+  \shortcut{Broadcast on/off}{\keys{\mod+Shift+B}}
+  \shortcut{Snippets}{\keys{\mod+Shift+S}}
+  \shortcut{Record on/off}{\keys{\mod+Shift+R}}}
+
+\sheet{amber}{\iTerminal\enspace In the terminal}{%
+  \shortcut{Copy selection}{\keys{\mod+C}}
+  \shortcut{Paste}{\keys{\mod+V}}
+  \shortcut{Find}{\keys{\mod+F}}
+  \shortcut{Next / previous match}{\kbd{Enter} / \keys{Shift+Enter}}
+  \shortcut{Scroll a page}{\keys{Shift+PageUp}}
+  \shortcut{Top / bottom}{\keys{Shift+Home} / \kbd{End}}
+  \shortcut{Previous / next prompt}{\keys{\mod+Shift+Up} / \kbd{Down}}
+  \shortcut{Open link}{\kbd{Ctrl}/\kbd{\ph{E1C4}} + click}}
+
+\sheet{pink}{\iMap\enspace Mouse moves}{%
+  \shortcut{Select word / line}{double / triple-click}
+  \shortcut{Extend selection}{\kbd{Shift} + click}
+  \shortcut{Select several profiles}{\kbd{Ctrl}/\kbd{\ph{E1C4}} + click}
+  \shortcut{Everything else}{right-click it}}
+\end{multicols}
+
+% =========================================================================================
+\chapter{Command-line options}\label{app:cli}
+\chapmeta{1 minute}{You'll script, demo and test with a few handy flags}
+
+\renewcommand\arraystretch{1.5}
+\begin{tabularx}{\linewidth}{@{}>{\leavevmode\ttfamily\color{ink}}p{52mm}X@{}}
+  \toprule
+  --data-dir DIR        & Use another data folder (portable installs, demos, testing).\\
+  --theme pro|midnight|light & Start with this theme.\\
+  --connect NAME        & Connect to a saved profile by name at startup. Repeat it for several.\\
+  --open WINDOW         & Open a window at startup: \code{settings}, \code{settings:security},
+                          \code{settings:diagnostics}, \code{snippets}, \code{keys}, \code{recordings}, \code{palette},
+                          \code{quick}…\\
+  --run-local CMD       & Open a local shell and run a command in it.\\
+  RUST\_LOG=debug        & (environment) More detail in \code{nexus.log}, and on the terminal you started from.\\
+  --version             & Print the version and exit.\\
+  \bottomrule
+\end{tabularx}
+
+\begin{sidequest}[How the screenshots in this guide were made]
+Every screenshot here is the real app, driven by \code{docs/guide/tools/screenshots.sh}: it starts throwaway
+SSH, IRC, VNC and GitHub-ish servers, fills a demo data folder, and runs Nexus Terminal headless with
+\code{--screenshot}, \code{--do} (run a palette command) and \code{--answer} (fill a password prompt). Change the app,
+rerun the script, rebuild the guide.
+\end{sidequest}
+
+% =========================================================================================
+\chapter{Glossary}\label{app:glossary}
+\chapmeta{dip in}{Words you might trip over, in one line each}
+
+\begin{multicols}{2}\small
+\begin{description}[leftmargin=0pt, itemsep=5pt]
+  \item[Agent] A background program holding your unlocked SSH keys, so you type the passphrase once.
+  \item[Asciicast] The file format for terminal recordings. Plays in Nexus Terminal and \code{asciinema}.
+  \item[Bastion / jump host] A server you go \emph{through} to reach the ones behind it.
+  \item[Baud rate] How fast a serial line talks. Both ends must agree.
+  \item[Broadcast] Typing into several sessions at once.
+  \item[Certificate authority] A key that vouches for other keys, so servers signed by it are trusted without a prompt.
+  \item[DTR / RTS] Serial control lines. Some boards use them for reset or flashing.
+  \item[Fingerprint] A short summary of a server's host key, used to spot imposters.
+  \item[Host key] A server's identity. Changes when it's rebuilt, or when someone's pretending.
+  \item[Keychain] Your operating system's password store.
+  \item[NLA] Network Level Authentication: Windows checks your password before building a desktop.
+  \item[OSC 133] The escape codes a shell uses to mark its prompts, which powers shell integration.
+  \item[Port forward] A tunnel carrying one TCP port through SSH.
+  \item[Profile] A saved connection.
+  \item[RAW TCP] A plain socket: bytes in, bytes out, no terminal rules.
+  \item[RDP] Microsoft's Remote Desktop Protocol, for Windows (and xrdp) desktops.
+  \item[SASL] How IRC networks log you in while you connect, instead of messaging NickServ afterwards.
+  \item[SFTP] File transfer over SSH.
+  \item[Snippet] A saved command, optionally with blanks to fill in.
+  \item[TOTP] Time-based one-time passwords: the six digits from your authenticator app.
+  \item[Trigger] A rule that watches output and reacts to a pattern.
+  \item[Vault] Nexus Terminal's encrypted password store, for when there's no keychain.
+  \item[VNC] A way of seeing and controlling another computer's desktop.
+\end{description}
+\end{multicols}
+
+\vfill
+\begin{center}
+\includegraphics[width=16mm]{img/logo.pdf}\par\vspace{6pt}
+{\heavy\color{ink}That's the lot.}\par
+{\small\color{muted}Go and connect to something. \iRocket}
+\end{center}

docs/guide/chapters/part1-start.tex

@@ -0,0 +1,247 @@
+\guidepart{accent}{Get going}{Get going}
+  {From zero to connected before your tea goes cold.}
+  {\partitem{\iRocket}{Five-minute start}
+   \partitem{\iMap}{The grand tour}
+   \partitem{\iList}{Profiles: your address book}}
+
+% =========================================================================================
+\chapter{Five-minute start}\label{ch:start}
+\chapmeta{5 minutes}{You'll be connected to something and know the one shortcut that matters}
+
+\begin{tldr}
+Install it, open it, press \keys{\mod+N}, fill in a host, hit \ui{Create \& Connect}. Done.
+Lost? Press \keys{\mod+K} and type what you want.
+\end{tldr}
+
+\section{Install it}
+
+Grab the zip for your machine from \code{dixon.cx/downloads/nexus}. They're named
+\code{NexusTerminal-<os>-<arch>.zip}, so a modern Mac wants \code{darwin-arm64} and most PCs want \code{amd64}.
+
+\begin{description}
+  \item[\iDesktop\enspace Windows] Unzip it and run \code{NexusTerminal-windows-amd64.exe}. No installer, no admin rights,
+    nothing in the registry. Pop it somewhere sensible like \code{C:\textbackslash Tools} and pin it to the taskbar.
+  \item[\iDesktop\enspace macOS] Unzip it and drag \code{NexusTerminal-darwin-arm64.app} into \ui{Applications}. If macOS
+    grumbles that it can't check the developer, right-click the app, choose \ui{Open}, then \ui{Open} again. You only
+    have to do that once.
+  \item[\iDesktop\enspace Linux] Unzip it and run \code{./install.sh}. It copies \code{nexus-terminal} into
+    \code{~/.local/bin} and adds a launcher entry with the icon, so it turns up in your app menu.
+    (Make sure \code{~/.local/bin} is on your \code{PATH}.)
+\end{description}
+
+\begin{sidequest}[Build it yourself]
+It's a single Rust program. With Rust installed: \code{cd rust \&\& cargo run --release}. The finished binary lands in
+\code{rust/target/release/nexus-terminal}. The build guide in \code{docs/build-and-release.md} has the full story.
+\end{sidequest}
+
+\section{Open it}
+
+The first time you open Nexus Terminal you get a calm, empty welcome screen. Three buttons, four shortcuts. That's it.
+
+\shot{welcome.png}{The welcome screen. Your saved connections will live down the left; here there are a few already.}
+
+\begin{headsup}[Got more than one computer?]
+Point \ui{Profile sync} at a shared folder and your connections follow you around. See
+\hyperref[ch:move]{Moving house} on p.\,\pageref{ch:move}.
+\end{headsup}
+
+\section{Make your first connection}
+
+\begin{enumerate}
+  \item Click \ui{New Connection}, or press \keys{\mod+N}.
+  \item Pick the protocol along the top: \proto[teal]{SSH}, \proto[amber]{Telnet}, \proto[violet]{RAW TCP},
+        \proto[slate]{GitHub}, \proto[rose]{VNC}, \proto[rose]{RDP}, \proto[amber]{IRC} or \proto[accent]{Serial}.
+  \item Fill in the \ui{General} bit: a \ui{Display Name} you'll recognise, the \ui{Host}, the \ui{Port}
+        and your \ui{Username}.
+  \item Click \ui{Create \& Connect}.
+\end{enumerate}
+
+That's genuinely it. A tab opens, you log in, and next time it's one click in the sidebar.
+
+\crop{editor-new.png}{1515}{40}{0}{70}{0.52\linewidth}{A brand-new SSH profile. Only the top few fields are needed to get going.}
+
+\begin{quickwin}
+Click \ui{Test} before you save. Nexus Terminal checks the host and port are reachable and tells you the
+round-trip time. If that fails, no amount of password-fiddling will help, so it's a great first check.
+\end{quickwin}
+
+\section{Two shortcuts for impatient people}
+
+\subsection{Quick Connect}
+Press \keys{\mod+Shift+Q}.
+For a one-off session you don't want to save. Pick SSH, Telnet, RAW, IRC or Serial, type the host (or serial
+device), hit \kbd{Enter}. Nothing gets saved.
+
+\crop{quick.png}{951}{620}{946}{481}{0.5\linewidth}{Quick Connect. In, out, nobody gets hurt.}
+
+\subsection{Local terminal}
+Click \ui{Local Machine} at the top of the sidebar (or \ui{Local} on the welcome screen) for a shell on
+\emph{this} computer. When you type \code{exit}, the tab says \code{[Exited - press enter to restart]}.
+Press \kbd{Enter} and you've got a fresh shell in the same tab.
+
+\section{The one shortcut to rule them all}
+
+\begin{center}
+\begin{tcolorbox}[enhanced, width=0.8\linewidth, arc=10pt, boxrule=0pt, colback=ink, fontupper=\color{white},
+  halign=center, top=10pt, bottom=10pt, drop fuzzy shadow]
+{\scalebox{2.4}{\keys{\mod+K}}}\par\vspace{6pt}\par\vspace{4pt}
+{\color{white!70!ink} The command palette. If you remember nothing else, remember this.}
+\end{tcolorbox}
+\end{center}
+
+Type a few letters of \emph{anything}: a connection name, a tab, ``theme'', ``split'', ``lock'', ``snippets''. Use
+\kbd{↑}\kbd{↓} to pick, \kbd{Enter} to go, \kbd{Esc} to bail. It's fuzzy, so ``atl'' finds \emph{atlas} and
+``sft'' finds the \emph{SFTP Browser}.
+
+\crop{palette.png}{755}{732}{733}{154}{0.72\linewidth}{The command palette: every connection, tab and action in one searchable list.}
+
+\begin{quickwin}[Your five-minute checklist]
+\begin{checklist}
+  \item Installed and opened Nexus Terminal
+  \item Opened a \ui{Local Machine} tab and typed \code{exit}, then \kbd{Enter} to get it back
+  \item Made a profile with \keys{\mod+N} and clicked \ui{Test}
+  \item Connected to it
+  \item Opened the palette with \keys{\mod+K} and found something by typing three letters
+\end{checklist}
+All ticked? You're officially more productive than you were five minutes ago. \iConfetti
+\end{quickwin}
+
+% =========================================================================================
+\chapter{The grand tour}\label{ch:tour}
+\chapmeta{4 minutes}{You'll know what every bit of the window is for}
+
+\begin{tldr}
+Connections on the left. Sessions in tabs across the top. The terminal in the middle. Status along the bottom.
+Everything else is one \keys{\mod+K} away.
+\end{tldr}
+
+\begin{annotated}{ssh.png}
+  \callout{1}{0.124}{0.022}
+  \callout{2}{0.66}{0.022}
+  \callout{3}{0.888}{0.022}
+  \callout{4}{0.22}{0.067}
+  \callout{5}{0.03}{0.152}
+  \callout{6}{0.53}{0.063}
+  \callout{7}{0.966}{0.063}
+  \callout{8}{0.62}{0.42}
+  \callout{9}{0.16}{0.945}
+  \callout{10}{0.26}{0.985}
+  \callout{11}{0.86}{0.985}
+\end{annotated}
+
+\begin{multicols}{2}\small
+\begin{description}[leftmargin=0pt, labelsep=0.4em]
+  \item[\num{1} Menus] \menu{File}, \menu{Session}, \menu{View} and \menu{Help}. Drag the title bar to move the
+        window; double-click it to maximise.
+  \item[\num{2} Palette] The search box is the command palette. Click it or press \keys{\mod+K}.
+  \item[\num{3} Light/dark] Flip between the dark and light themes in one click.
+  \item[\num{4} Search] Fuzzy-search your connections by name, host, tag or protocol.
+  \item[\num{5} Sections] \ui{Local Machine}, \ui{Favourites} \iStar, \ui{Recent} (your last five), then one section
+        per group. Click a header to fold it away.
+  \item[\num{6} Tabs] One per session, with a coloured state dot, protocol badge and close button. SSH tabs get a
+        little \iFolder{} for files. A blue dot means ``new output while you weren't looking''.
+  \item[\num{7} New \& broadcast] \ui{+} opens a new connection; \iBroadcast{} toggles broadcast mode.
+  \item[\num{8} Workspace] Your terminal (or IRC chat, VNC desktop, GitHub list…). Split it into panes, too.
+  \item[\num{9} Footer] New connection, palette, import, export, recordings and settings.
+  \item[\num{10} Status] State, protocol and live latency for SSH. Shows \ui{REC} while recording and
+        \ui{BROADCAST} when broadcasting.
+  \item[\num{11} Sessions \& vault] How many sessions are connected and whether the vault is locked. Click the vault to
+        open security settings.
+\end{description}
+\end{multicols}
+
+\begin{protip}
+Drag the right-hand edge of the sidebar to make it wider or narrower. Toasts (the little pop-up messages in the
+top-right) tidy themselves away after a few seconds; click \ui{×} if you're impatient.
+\end{protip}
+
+\section{Three looks}
+
+Nexus Terminal comes in \ui{Pro} (the default, a soft charcoal), \ui{Midnight} (darker, bluer, for 2\,a.m.
+deploys) and \ui{Light} (for sunny days and projectors). Switch with the \iBulb{} button in the title bar, the
+\menu{View} menu, or type ``theme'' into the palette.
+
+\shotpair{welcome-midnight.png}{Midnight}{ssh-light.png}{Light, with a session open}
+
+The \emph{terminal} has its own colour schemes too: eleven of them, including \ui{Dracula}, \ui{Nord},
+\ui{Tokyo Night}, \ui{Catppuccin Mocha} and \ui{Rosé Pine}. Those live in \menu{Settings\then Terminal} and the \menu{View} menu.
+
+% =========================================================================================
+\chapter{Profiles: your address book}\label{ch:profiles}
+\chapmeta{6 minutes}{You'll keep dozens of connections tidy without thinking about it}
+
+\begin{tldr}
+A \emph{profile} is a saved connection. Give it a name and a group, star the ones you use daily, and
+right-click for everything else. Ctrl-click to select lots at once.
+\end{tldr}
+
+\section{Create, edit, copy}
+
+\begin{itemize}
+  \item \textbf{New:} \ui{+} in the sidebar footer or tab strip, \keys{\mod+N}, or right-click a group header and choose
+        \ui{New connection in …} (it lands in that group automatically).
+  \item \textbf{Edit:} double-click a profile, or right-click\then\ui{Edit}. The editor slides in on the right.
+  \item \textbf{Copy:} right-click\then\ui{Duplicate}. Great for ``same as web-01 but web-02''.
+  \item \textbf{Delete:} right-click\then\ui{Delete}. This also deletes the saved passwords for that profile.
+\end{itemize}
+
+\crop{editor-ssh.png}{1515}{40}{0}{70}{0.52\linewidth}{Editing an existing SSH profile. The editor scrolls; sections are grouped so you can ignore most of them.}
+
+\subsection{What goes in a profile}
+
+Every profile has the same \ui{General} section, then sections specific to its protocol (Part 2 covers each
+one). The common bits are:
+
+\renewcommand\arraystretch{1.4}
+\begin{tabularx}{\linewidth}{@{}>{\leavevmode\heavy\color{ink}}p{32mm}X@{}}
+  \toprule
+  Display Name & What you'll see in the sidebar. Make it obvious: ``db-primary'', not ``server 3''.\\
+  Host / Port  & Where to connect. Serial profiles have a \ui{Device} instead.\\
+  Group        & Pick an existing group or type a new name to create one.\\
+  Description  & One line shown on hover.\\
+  Terminal     & Font, size (8–36), scrollback (0–100\,000 lines) and cursor style, just for this profile.\\
+  Tags \& Notes & Comma-separated tags (searchable!) and free-form notes for future-you.\\
+  \bottomrule
+\end{tabularx}
+
+Each protocol adds its own sections underneath. Here are four of them side by side; Part~2 goes through each one.
+
+\begin{center}
+\newcommand\mini[2]{\begin{minipage}[t]{0.24\linewidth}\centering\includegraphics[width=\linewidth, trim=1515 600 0 70, clip]{img/#1}\par\vspace{2pt}{\scriptsize\color{muted}#2}\end{minipage}}
+\mini{editor-telnet.png}{Telnet}\hfill\mini{editor-raw.png}{RAW TCP}\hfill\mini{editor-vnc.png}{VNC}\hfill\mini{editor-irc.png}{IRC}
+\end{center}
+
+\begin{protip}[Tags are secretly brilliant]
+Tag things by where they live and what they do (\code{eu-west}, \code{db}, \code{customer-x}). The sidebar search
+matches tags, so typing ``db'' instantly narrows hundreds of profiles to the database servers.
+\end{protip}
+
+\section{Favourites, groups and Recent}
+
+\begin{itemize}
+  \item Right-click\then\ui{Add to Favourites} pins a profile into the \ui{\iStar\ Favourites} section at the top.
+  \item \ui{Recent} always shows the last five things you connected to. You don't have to do anything.
+  \item Groups are just the \ui{Group} field. No group? It goes in \ui{Ungrouped}.
+\end{itemize}
+
+\section{Do lots at once}
+
+Hold \kbd{Ctrl} (\kbd{\ph{E1C4}} on a Mac) and click several profiles. A bar appears at the bottom of the sidebar:
+
+\begin{center}\small
+\begin{tabular}{@{}ll@{\qquad}ll@{}}
+  \ui{Connect all} & opens them all in tabs & \ui{Move group} & moves them (blank = Ungrouped)\\
+  \ui{Disconnect}  & closes their sessions & \ui{Delete} & deletes them (asks first)\\
+  \ui{Tags}        & add or replace tags & \ui{Clear} & forget the selection\\
+\end{tabular}
+\end{center}
+
+\begin{quickwin}
+Select every web server, choose \ui{Connect all}, then turn on broadcast (\keys{\mod+Shift+B}). You're now typing into
+all of them at once. Chapter~\ref{ch:repeat} has the details, and the safety advice.
+\end{quickwin}
+
+\section{``It's already open…''}
+
+Click a profile that already has a live session and Nexus Terminal asks whether to \ui{Use Existing} (jump to that
+tab), open a \ui{New Connection} alongside it, or \ui{Cancel}. No more accidental duplicate sessions.

docs/guide/chapters/part2-connect.tex

@@ -0,0 +1,333 @@
+\guidepart{teal}{Connect}{Connect to all the things}
+  {Nine ways in. Pick the one you need; skip the rest.}
+  {\partitem{\iTerminal}{SSH: the big one}
+   \partitem{\iUsb}{Serial: cables and consoles}
+   \partitem{\iPlug}{Telnet and RAW TCP}
+   \partitem{\iDesktop}{VNC remote desktops}
+   \partitem{\iDesktop}{RDP: Windows desktops}
+   \partitem{\iChat}{IRC}
+   \partitem{\iGithub}{GitHub}}
+
+% =========================================================================================
+\chapter{SSH: the big one}\label{ch:ssh}
+\chapmeta{10 minutes (or 2 for the basics)}{You'll log in with keys, hop through bastions and never type a 2FA code again}
+
+\begin{tldr}
+Host, username, key, done. Everything else (jump hosts, proxies, forwards, 2FA, login scripts) is optional and
+lives in its own fold-away section of the editor. Open only the ones you need.
+\end{tldr}
+
+\begin{glance}{teal}{SSH}
+  Default port & 22\\
+  Logs in with & Password, public key, keyboard-interactive, SSH agent\\
+  Extras       & SFTP file browser, port forwards, live latency, agent forwarding, TOTP 2FA\\
+  Good for     & Servers, VMs, Raspberry Pis, anything with \code{sshd}\\
+\end{glance}
+
+\section{The two-minute version}
+
+\begin{enumerate}
+  \item \keys{\mod+N}, leave the protocol on \proto[teal]{SSH}.
+  \item \ui{Host}, \ui{Username}. Leave the port on 22 unless you know otherwise.
+  \item Under \ui{Key \& Passphrase}, pick your key from the suggestions (Nexus Terminal lists the keys in your
+        \code{\textasciitilde/.ssh} folder) and check for a little green \ui{Key verified}.
+  \item \ui{Create \& Connect}. The first time, you'll be asked to trust the server's host key. Say yes if you
+        were expecting it.
+\end{enumerate}
+
+\crop{hostkey.png}{842}{720}{845}{589}{0.66\linewidth}{First time connecting? You'll be shown the server's fingerprint. \ui{Accept \& Save} if it's the server you meant.}
+
+\begin{headsup}
+Type the full path to a key if you're not using the suggestions. Nexus Terminal doesn't expand \code{\textasciitilde}
+in that box, so write \code{/home/you/.ssh/id\_ed25519} (or \code{C:\textbackslash Users\textbackslash you\textbackslash .ssh\textbackslash id\_ed25519}).
+\end{headsup}
+
+\section{How it logs in}
+
+Under \ui{Authentication}, tick which \ui{Auth Methods} to try: \ui{Public key}, \ui{Password} and
+\ui{Keyboard-interactive}. Under \ui{SSH Agent}, tick \ui{Use SSH Agent for Authentication} to use keys already
+loaded into \code{ssh-agent} (or Pageant, or the Windows OpenSSH agent).
+
+Got an SSH \emph{user certificate}? Put it next to the key with the usual name (\code{id\_ed25519-cert.pub} beside
+\code{id\_ed25519}) and Nexus Terminal presents it automatically. Servers that hand out \emph{host} certificates are
+covered in \hyperref[ch:hostkeys]{Host keys} (p.\,\pageref{ch:hostkeys}).
+
+Every password and passphrase has a \emph{mode}: save it securely, remember it until you quit, or ask every time.
+That's all explained in \hyperref[ch:secrets]{Passwords \& the vault} (p.\,\pageref{ch:secrets}).
+
+\begin{protip}[Agent forwarding]
+Tick \ui{Forward Agent to Remote} (it's \code{ssh -A}) and you can \code{git pull} or hop onwards from the server using
+the keys on \emph{your} machine. Only do it on servers you trust: anyone with root there can use your agent while
+you're connected.
+\end{protip}
+
+\section{Jump hosts: getting through the bastion}
+
+Lots of servers hide behind a bastion. Add one or more hops under \ui{Jump Hosts}, each with its own user, host,
+port and optional key. Nexus Terminal tunnels through them in order, so the chain
+\textit{you\then bastion\then internal-box\then db-primary} is just three rows.
+
+\section{Proxies}
+
+Stuck behind a corporate proxy? Under \ui{Proxy}, choose \ui{SOCKS5} or \ui{HTTP CONNECT} and fill in the host,
+port and (optional) username and password. The proxy is used to reach the SSH server, or the first jump host if
+you have some.
+
+\section{2FA without the phone faff}\label{sec:totp}
+
+If your server asks for a one-time code, paste the Base32 TOTP secret (the text version of the QR code) into
+\ui{TOTP Secret} and hit \ui{Save}. From then on, Nexus Terminal answers the ``Verification code:'' prompt itself.
+\ui{Test} shows today's code so you can check it matches your phone.
+
+\begin{headsup}
+Save the profile first, then save the TOTP secret. And make sure your computer's clock is right: TOTP codes are
+time-based, so a clock that's a minute out will produce wrong codes.
+\end{headsup}
+
+\section{Do things automatically on login}
+
+\begin{description}
+  \item[Startup] A \ui{Startup Command} to run once you're in (say, \code{tmux attach}), plus
+        \ui{Environment Variables} as \code{KEY=VALUE}, one per line.
+  \item[Login Script] For old-school boxes that ask questions. Add steps: \ui{Wait for} some text, then
+        \ui{Send} a reply. Repeat as needed.
+\end{description}
+
+\section{Keeping it alive}
+
+Under \ui{Advanced}: the \ui{Terminal Type}, the \ui{Keepalive Interval} and \ui{Max Missed Keepalives}, compression,
+and \ui{Auto-Reconnect} with a maximum number of attempts (1–20). Reconnection backs off politely: 1\,s, 2\,s,
+4\,s… up to 30\,s.
+
+\begin{sidequest}[What's that number in the status bar?]
+For SSH sessions the status bar shows live latency, the round trip to the server. Green is snappy. If it's
+in the hundreds and your typing feels sticky, it's the network, not you.
+\end{sidequest}
+
+% =========================================================================================
+\chapter{Serial: cables and consoles}\label{ch:serial}
+\chapmeta{4 minutes}{You'll be talking to a switch, router or microcontroller over USB}
+
+\begin{tldr}
+Plug in the adapter, pick the device, match the baud rate. 115200 8N1 is the default and usually right.
+Right-click the tab to send a break or wiggle DTR/RTS.
+\end{tldr}
+
+\begin{glance}{accent}{Serial}
+  Device       & \code{/dev/ttyUSB0}, \code{/dev/cu.usbserial-…} or \code{COM3}\\
+  Defaults     & 115200 baud, 8 data bits, no parity, 1 stop bit, no flow control, CR line endings, DTR and RTS on\\
+  Extras       & Send Break, toggle DTR/RTS, auto-reconnect when the cable comes back\\
+  Good for     & Network gear consoles, Arduinos, ESP32s, Raspberry Pi UARTs, 3D printers\\
+\end{glance}
+
+\crop{editor-serial.png}{1515}{40}{0}{70}{0.52\linewidth}{A serial profile for a switch console at 9600 baud. Click refresh after plugging in an adapter.}
+
+\section{Setting it up}
+
+\begin{description}
+  \item[Device] Pick it from the list (hit refresh after plugging in) or type the path.
+  \item[Line Settings] \ui{Baud Rate} (a preset from 300 to 1\,000\,000, or \ui{Custom}), \ui{Data Bits} (5–8),
+        \ui{Parity} (none, odd, even), \ui{Stop Bits} (1 or 2) and \ui{Flow Control} (none, XON/XOFF, RTS/CTS).
+  \item[Behaviour] \ui{Line Ending}, \ui{Encoding}, \ui{Local Echo} (for devices that don't echo what you type),
+        \ui{Assert DTR on connect}, \ui{Assert RTS on connect} and \ui{Auto-reconnect}.
+\end{description}
+
+\section{While you're connected}
+
+Right-click the tab for \ui{Send Break} (handy for getting into a router's ROMMON) and to toggle \ui{DTR} and
+\ui{RTS} (handy for resetting boards that wire those to reset). Pull the cable out and the session disconnects; with
+auto-reconnect on, it picks up again when you plug it back in.
+
+Serial tabs are proper terminals, so recording, triggers, broadcast, snippets, find and split panes all work.
+
+\begin{headsup}[Gibberish on screen?]
+Garbled characters nearly always mean the baud rate, parity or stop bits don't match the device. Check the
+device's manual. 9600 and 115200 are the usual suspects.
+\end{headsup}
+
+\begin{protip}[Linux and macOS quirks]
+On Linux, add yourself to the \code{dialout} group (\code{uucp} on some distributions) and log out and in again.
+On a Mac, use the \code{/dev/cu.*} device, not \code{/dev/tty.*}.
+\end{protip}
+
+% =========================================================================================
+\chapter{Telnet and RAW TCP}\label{ch:raw}
+\chapmeta{4 minutes}{You'll poke at old kit and raw sockets without reaching for netcat}
+
+\begin{tldr}
+Telnet is a terminal for old devices. RAW is a packet-level conversation with any TCP port, with a hex view.
+\end{tldr}
+
+\section{Telnet}
+
+\begin{glance}{amber}{Telnet}
+  Default port & 23\\
+  Options      & Local echo, line mode, terminal type, encoding (UTF-8, ASCII, ISO 8859-1), line endings, login script\\
+  Extras       & Send Break from the tab menu, \ui{Debug Negotiation} for when options go wrong\\
+\end{glance}
+
+\begin{danger}[Telnet is plain text]
+Everything, including your password, crosses the network unencrypted. Fine on a lab bench, not fine over the
+internet or café Wi-Fi.
+\end{danger}
+
+\section{RAW TCP}
+
+RAW connects to any TCP port and shows you exactly what goes back and forth. Instead of a terminal you get a
+traffic log with \ui{Text}, \ui{Hex} and \ui{Split} views.
+
+\shot{raw.png}{A RAW session to a chatty sensor, with timestamps and direction markers turned on.}
+
+\begin{itemize}
+  \item \textbf{Send bar:} pick \ui{Text}, \ui{Hex} or \ui{Escaped} (\code{\textbackslash r\textbackslash n} and friends),
+        type, press \kbd{Enter}. One-click buttons send \ui{NUL}, \ui{CR}, \ui{LF}, \ui{ETX} and \ui{EOT}.
+  \item \textbf{Presets:} save payloads you send often in the profile under \ui{Payload Presets}, then pick them from
+        \ui{Presets…}.
+  \item \textbf{Capture:} \ui{Pause}, \ui{Clear}, and \ui{Save} (writes the whole conversation as JSON).
+  \item \textbf{Profile options:} encoding (UTF-8, ASCII, Hex), line ending, timestamps, direction, timeouts and
+        auto-reconnect.
+\end{itemize}
+
+\begin{quickwin}
+Point a RAW profile at a web server on port 80 and send \code{HEAD / HTTP/1.0\textbackslash r\textbackslash n\textbackslash r\textbackslash n}
+in \ui{Escaped} mode. Instant HTTP headers, no browser required.
+\end{quickwin}
+
+% =========================================================================================
+\chapter{VNC remote desktops}\label{ch:vnc}
+\chapmeta{4 minutes}{You'll see and drive a remote desktop, safely}
+
+\begin{tldr}
+VNC shows you another computer's screen. Tunnel it through SSH (tick a box), because plain VNC isn't encrypted.
+\end{tldr}
+
+\begin{glance}{rose}{VNC}
+  Default port & 5900 (plus the display number: display \code{:1} is 5901)\\
+  Display      & \ui{View Only}, \ui{Scale to Fit}, \ui{Shared Session}, \ui{Quality (0-9)}\\
+  Security     & Optional SSH tunnel with password, key or agent login\\
+\end{glance}
+
+\shot{vnc.png}{A remote desktop, scaled to fit the tab.}
+
+\section{The toolbar}
+
+Connection state and desktop size on the left. On the right: switch between scaled and 1:1, refresh,
+\ui{Paste Clipboard} (sends your clipboard to the remote machine) and \ui{Ctrl+Alt+Del}. Click the desktop to give
+it your keyboard. Anything the remote machine copies lands on your clipboard automatically.
+
+\section{Tunnel it}
+
+Tick \ui{Enable SSH Tunnel} and fill in the SSH host, port, username and login method. The VNC traffic then
+travels inside an encrypted SSH connection. If you connect to a VNC profile \emph{without} a tunnel, Nexus Terminal
+warns you and offers \ui{Connect Anyway}, \ui{Edit Profile} or \ui{Cancel}.
+
+\begin{headsup}[Connecting to a Mac?]
+Turn on \ui{VNC viewers may control screen with password} in macOS Screen Sharing settings. Nexus Terminal uses
+standard VNC password authentication, not Apple's own login method.
+\end{headsup}
+
+% =========================================================================================
+\chapter{RDP: Windows desktops}\label{ch:rdp}
+\chapmeta{4 minutes}{You'll be on a Windows (or xrdp) desktop without leaving Nexus Terminal}
+
+\begin{tldr}
+Host, username, password. Nexus Terminal logs on with NLA, pins the server's certificate like an SSH host key, and
+can go through a proxy, an SSH tunnel or an RD Gateway.
+\end{tldr}
+
+\begin{glance}{rose}{RDP}
+  Default port & 3389\\
+  Logs in with & NLA (NTLM, or Kerberos with a KDC); \ui{Allow servers without NLA} for xrdp\\
+  Display      & \ui{Scale to Fit}, fixed size, \ui{Resize With Tab}\\
+  Extras       & Clipboard both ways, remote audio, printer, shared folder\\
+  Getting there & SOCKS5 or HTTP proxy, SSH tunnel, RD Gateway (experimental)\\
+\end{glance}
+
+\shot{rdp.png}{An xrdp desktop in a tab. Ctrl+Alt+Del and Paste Clipboard sit on the toolbar.}
+
+\section{Setting it up}
+
+\begin{enumerate}
+  \item \keys{\mod+N}, protocol \proto[rose]{RDP}.
+  \item \ui{Host} and \ui{Username}; add a \ui{Domain} if your account has one.
+  \item Pick how the password is kept (save it, remember it until you quit, or ask every time).
+  \item \ui{Create \& Connect}. The first time, you're shown the server's certificate fingerprint. Accept it if
+        it's the machine you meant.
+\end{enumerate}
+
+Windows checks your password \emph{before} it builds a desktop (Network Level Authentication), so a typo fails fast.
+Linux machines running xrdp don't speak NLA: tick \ui{Allow servers without NLA} for those. In an Active Directory
+shop, set a \ui{Kerberos KDC} (\code{host} or \code{host:port}) and use your realm as the domain.
+
+\begin{headsup}[A changed certificate]
+RDP servers mostly use self-signed certificates, so Nexus Terminal remembers the fingerprint in
+\ui{Known Hosts}. If it changes you get \ui{Reject}, \ui{Accept Once} or \ui{Accept \& Update}, and nothing (not even your
+password) is sent until you choose.
+\end{headsup}
+
+\section{While you're connected}
+
+It works like the VNC viewer: click the desktop to give it your keyboard, \ui{Ctrl+Alt+Del} sends exactly that, and
+text you copy on either side turns up on the other. With \ui{Resize With Tab} the remote desktop follows the tab's
+size (Windows does this; other servers are scaled).
+
+Under \ui{Devices}: \ui{Play Remote Audio}; \ui{Redirect Printer}, which adds a \emph{Nexus Terminal} printer whose jobs
+land as PostScript files in your Downloads folder; and (Linux and macOS) a \ui{Shared Folder} that shows up remotely as
+a drive called Nexus. The server can read and change that folder, and nothing outside it.
+
+\section{Getting through}
+
+Pick \emph{one} of: a \ui{Proxy} (SOCKS5 or HTTP CONNECT), an \ui{SSH Tunnel} (same as VNC), or an \ui{RD Gateway}
+(experimental: the gateway needs a proper public certificate and Basic authentication over HTTPS).
+
+% =========================================================================================
+\chapter{IRC}\label{ch:irc}
+\chapmeta{3 minutes}{You'll be chatting in your project's channels from the same window as your servers}
+
+\begin{tldr}
+Nick, server, rooms to join. Tabs for each room, \code{/commands} as you'd expect, \kbd{Tab} completes nicks.
+\end{tldr}
+
+\begin{glance}{amber}{IRC}
+  Default port & 6667, or 6697 with \ui{Use TLS} (use TLS!)\\
+  Logs in with & SASL PLAIN (most networks want this now), or NickServ identify\\
+  Extras       & Auto-join rooms, room browser, real message times (IRCv3 server-time), SSH tunnel\\
+\end{glance}
+
+\shot{irc.png}{Chatting in \#nexus. Rooms down the right, users in the room below them.}
+
+\begin{itemize}
+  \item A \ui{Server} tab plus one per room or private conversation. A dot means unread messages.
+  \item Commands: \code{/join}, \code{/part}, \code{/msg}, \code{/me}, \code{/notice}, \code{/nick}, \code{/topic},
+        \code{/list}, \code{/names}, \code{/whois}, \code{/who}, \code{/raw}, \code{/quit} and \code{/help}.
+  \item \kbd{Tab} completes a nick; click a nick to mention them.
+  \item The side panel lists your rooms, a room browser with a filter (click to join) and who's in the current room.
+\end{itemize}
+
+% =========================================================================================
+\chapter{GitHub}\label{ch:github}
+\chapmeta{2 minutes}{You'll see all your repositories, freshest first}
+
+\crop{editor-github.png}{1515}{780}{0}{70}{0.5\linewidth}{A GitHub profile: just the API address and a token.}
+
+\begin{tldr}
+Paste a personal access token with the \code{repo} scope. Get a tidy, filterable list of every repository you can see.
+\end{tldr}
+
+\shot{github.png}{Repositories grouped by owner, with the latest commit and who made it.}
+
+\begin{itemize}
+  \item Grouped by owner or organisation, sorted by most recent activity.
+  \item Badges for \proto[rose]{Private}, \proto[violet]{Fork} and \proto[amber]{Archived}, plus language and stars.
+  \item Filter box, \ui{Refresh now}, \ui{Visit} (opens in your browser) and \ui{ZIP} (downloads an archive).
+  \item Works with GitHub Enterprise: set \ui{API Base URL} to your server's API address. Refreshes every 60–3600 seconds.
+\end{itemize}
+
+% =========================================================================================
+\chapter{Your own computer}\label{ch:local}
+\chapmeta{1 minute}{You'll stop alt-tabbing to a separate terminal app}
+
+Click \ui{Local Machine} for a shell on this computer. It uses your system's default shell unless you choose
+another in \menu{Settings\then General\then Local shell} (\code{pwsh}, \code{zsh}, \code{fish}, whatever you fancy).
+
+\shot[0.86\linewidth]{local.png}{A local shell, with all the same terminal powers as SSH.}

docs/guide/chapters/part3-faster.tex

@@ -0,0 +1,264 @@
+\guidepart{violet}{Work faster}{Work faster}
+  {Fewer clicks, less typing, more getting on with it.}
+  {\partitem{\iSplit}{Tabs and split panes}
+   \partitem{\iKeyboard}{Terminal superpowers}
+   \partitem{\iWand}{Never type it twice}
+   \partitem{\iFolder}{Files: SFTP and drag-and-drop}
+   \partitem{\iArrows}{Port forwards}
+   \partitem{\iFilm}{Recordings}}
+
+% =========================================================================================
+\chapter{Tabs and split panes}\label{ch:tabs}
+\chapmeta{4 minutes}{You'll juggle a dozen sessions without losing any of them}
+
+\begin{tldr}
+Right-click a tab for everything. \keys{\mod+Shift+D} splits right, \keys{\mod+Shift+E} splits down.
+\keys{\mod+1} to \keys{\mod+9} jump straight to a tab.
+\end{tldr}
+
+\section{Tabs}
+
+\begin{description}
+  \item[Move] Drag tabs about, or right-click\then\ui{Move Left} / \ui{Move Right}.
+  \item[Pin] Right-click\then\ui{Pin}. Pinned tabs stay at the front.
+  \item[Rename] Right-click\then\ui{Rename}. ``prod DB, DON'T TOUCH'' is a perfectly valid tab name.
+  \item[Duplicate] Opens another session to the same profile.
+  \item[Reconnect] Does what it says.
+  \item[Peek] Hover a tab for its name, host, state and when it connected.
+  \item[Close] The \ui{×}, \keys{\mod+W}, or right-click\then\ui{Close}. Connected tabs ask first (you can turn that
+        off in Settings).
+  \item[Switch] \keys{\mod+Tab} and \keys{\mod+Shift+Tab}, or \keys{\mod+1} to \keys{\mod+9}.
+\end{description}
+
+Lots of tabs? Scroll the tab strip with your mouse wheel or trackpad. Quit with a dozen open and they're all back next
+time: \ui{Restore tabs at launch} (on by default) reconnects saved profiles and reopens local shells, splits and all,
+in the folder they were in.
+
+\section{Split panes}
+
+Want two sessions side by side? Split the focused pane right with \keys{\mod+Shift+D} or down with
+\keys{\mod+Shift+E} (also in the \menu{Session} menu, the right-click menu and the palette). The new pane asks
+what to open: \ui{Local Machine} or any of your terminal profiles.
+
+\shot{split.png}{A fresh split. Pick what goes in the new pane.}
+
+Drag a divider to resize. Click \ui{×} on a pane's header to close it and its neighbour takes the space. Closing
+the tab closes every pane in it.
+
+\begin{quickwin}
+Split right, open \code{htop} on one side and tail a log on the other. Now you look like a hacker in a film.
+\end{quickwin}
+
+% =========================================================================================
+\chapter{Terminal superpowers}\label{ch:terminal}
+\chapmeta{4 minutes}{You'll copy, search and scroll like you've used it for years}
+
+\begin{tldr}
+Select to copy, \keys{\mod+F} to search, Ctrl/\ph{E1C4}-click links. Right-click for the rest.
+\end{tldr}
+
+\section{Keyboard and mouse}
+
+\renewcommand\arraystretch{1.45}
+\begin{tabularx}{\linewidth}{@{}>{\leavevmode\heavy\color{ink}}p{24mm}X@{}}
+  \toprule
+  Copy   & Select text, then \keys{\mod+C}. Nothing selected? \keys{Ctrl+C} interrupts the program as usual.\\
+  Paste  & \keys{\mod+V}. Pastes are bracketed when the program asks for it, so editors won't auto-indent your paste
+           into a staircase. Pasting several lines into a shell asks first (turn that off in Settings).\\
+  Select & Drag for a range, double-click a word, triple-click a line, \kbd{Shift}-click to extend.\\
+  Links  & Hold \kbd{Ctrl} (\kbd{\ph{E1C4}}) and click a URL to open it in your browser. Real hyperlinks that
+           programs print (\code{ls --hyperlink}, compilers) get a dotted underline; hover to see where they really go.\\
+  Scroll & Mouse wheel, or \keys{Shift+PageUp}, \keys{Shift+PageDown}, \keys{Shift+Home}, \keys{Shift+End}.\\
+  \bottomrule
+\end{tabularx}
+
+\begin{sidequest}[Why does the scroll wheel move the cursor in less?]
+Full-screen programs (\code{less}, \code{vim}, \code{tmux}, \code{byobu}) use the terminal's ``alternate screen'', where the
+wheel sends arrow keys instead of scrolling. Programs with mouse support (\code{htop}, \code{vim} with
+\code{mouse=a}, \code{tmux} mouse mode) get your clicks directly. That's normal terminal behaviour, not a bug.
+\end{sidequest}
+
+\section{The right-click menu}
+
+\ui{Copy}, \ui{Paste}, \ui{Select All}, \ui{Find}, \ui{Previous Prompt} / \ui{Next Prompt}, \ui{Copy Last Command
+Output}, \ui{Send Snippet}, \ui{Port Forwards} (SSH), \ui{Split Right}, \ui{Split Down}, \ui{Export Output} (saves the
+whole scrollback as a text file), \ui{Clear} and \ui{Reset}.
+
+\section{Shell integration}
+
+If your shell marks its prompts (fish 4, Starship and Powerlevel10k do already), Nexus Terminal knows where every
+command starts and stops. \keys{\mod+Shift+Up} and \keys{\mod+Shift+Down} jump from prompt to prompt,
+\ui{Copy Last Command Output} grabs just what the last command printed, and a thin bar beside each prompt shows how it
+went: green for success, red for failure. Hover the bar for the exit code and how long it took.
+
+\shot{shell-integration.png}{\code{make test} failed (red bar), \code{ls} worked (green bar).}
+
+For bash, add this to \code{\textasciitilde/.bashrc} on the machine the shell runs on (the user manual has the zsh
+version):
+
+\begin{verbatim}
+PS0='\[\e]133;C\a\]'
+PROMPT_COMMAND='printf "\033]133;D;%s\007" "$?"; '"${PROMPT_COMMAND}"
+PS1='\[\e]133;A\a\]'"$PS1"'\[\e]133;B\a\]'
+\end{verbatim}
+
+\section{Pictures in the terminal}
+
+Programs that print images the iTerm2 way (\code{imgcat}, \code{wezterm imgcat}, \code{chafa -f iterm}) show PNG,
+JPEG and GIF images right in the scrollback. They scroll with the text and never spill past the edge.
+
+\shot{inline-image.png}{An image printed by a script, with the text carrying on underneath.}
+
+\section{Find}
+
+\keys{\mod+F} opens the find bar. Toggle \ui{Aa} for case-sensitive and \ui{.*} for regular expressions.
+\kbd{Enter} for the next match, \keys{Shift+Enter} for the previous one, \kbd{Esc} to close. It shows
+``3 of 17'' so you know where you are.
+
+\section{When the connection drops}
+
+The pane dims and shows a \ui{Disconnected} card with \ui{Reconnect} and \ui{Close}. If auto-reconnect is on,
+it says \ui{Reconnecting…} with a \ui{Cancel} button, and a toast tells you which attempt it's on.
+
+If the problem was a password or host key, you get a friendly dialog explaining what happened, with
+\ui{Retry}, \ui{Edit Profile}, \ui{Known Hosts} (for host-key trouble) and \ui{Close}.
+
+% =========================================================================================
+\chapter{Never type it twice}\label{ch:repeat}
+\chapmeta{6 minutes}{You'll stop retyping the same commands, and let Nexus Terminal watch the logs for you}
+
+\begin{tldr}
+\textbf{Snippets} store commands. \textbf{Broadcast} types into many sessions at once. \textbf{Triggers} watch output and
+tap you on the shoulder.
+\end{tldr}
+
+\section{Snippets: \keys{\mod+Shift+S}}
+
+Save commands you use a lot, with a name, description and folder. Search them, click
+\ui{Send to Session}, and the command is typed into the active session followed by \kbd{Enter}.
+
+\crop{snippets.png}{633}{384}{611}{402}{0.8\linewidth}{The snippet library, organised into folders.}
+
+Snippets can have blanks to fill in:
+
+\begin{itemize}
+  \item \code{\{\{hostname\}\}}, \code{\{\{date\}\}}, \code{\{\{time\}\}} and \code{\{\{timestamp\}\}} are filled in for you.
+  \item Anything else, like \code{\{\{service\}\}}, is asked for when you send it.
+\end{itemize}
+
+So \code{journalctl -fu \{\{service\}\}} asks ``service?'' and tails whichever one you type.
+
+\section{Broadcast: \keys{\mod+Shift+B}}
+
+Turn broadcast on and everything you type goes to \emph{every} connected terminal. The status bar shows
+\ui{BROADCAST} so you can't forget it's on.
+
+\shot{broadcast.png}{Broadcast is on: the status bar says so in no uncertain terms.}
+
+To broadcast to only some sessions, right-click the \iBroadcast{} button (or \menu{Session\then Broadcast
+targets…}), tick the ones you want and click \ui{Apply \& Enable}.
+
+\begin{danger}[With great power…]
+Broadcast doesn't care which tab you \emph{meant}. Double-check the target list before you type anything
+destructive. \code{sudo reboot} into twenty servers is very efficient and very memorable.
+\end{danger}
+
+\section{Triggers: let it watch for you}
+
+\menu{Session\then Trigger Rules} (or the palette). Each rule has a pattern (plain text or a regular
+expression), a case-sensitivity switch, an on/off switch, and an action:
+
+\begin{center}\small
+\begin{tabular}{@{}ll@{}}
+  \ui{Notify} & shows a toast\\
+  \ui{Highlight tab} & briefly outlines the pane\\
+  \ui{Notify + Highlight} & both\\
+  \ui{Sound} & asks your OS for attention (a bouncing dock icon or flashing taskbar button) and shows a toast\\
+\end{tabular}
+\end{center}
+
+\crop{triggers.png}{725}{610}{725}{625}{0.75\linewidth}{Three rules: shout about errors, ping when a build finishes, and one switched off for now.}
+
+Rules check each complete line of output, with colours stripped out first.
+
+\begin{quickwin}
+Add a rule for \code{BUILD SUCCESSFUL} with the \ui{Sound} action, start a long build, and go and make a cup of tea.
+Nexus Terminal will tell you when it's done. (Or \code{(?i)error|fatal} for the opposite.)
+\end{quickwin}
+
+% =========================================================================================
+\chapter{Files: SFTP and drag-and-drop}\label{ch:files}
+\chapmeta{4 minutes}{You'll move files to and from servers without leaving the terminal}
+
+\begin{tldr}
+Click the \iFolder{} on an SSH tab. Or drop a file onto the terminal and choose \ui{Upload}.
+\end{tldr}
+
+\section{The SFTP browser}
+
+Click the \iFolder{} folder icon on an SSH tab, \menu{Session\then SFTP browser}, or type ``sftp'' in the palette.
+It opens in the side dock next to your terminal, in the folder your shell is in if the shell reports it
+(fish does; bash and zsh need a one-line hook, see the user manual).
+
+\shot{sftp.png}{Browsing the server's files next to the terminal.}
+
+\begin{itemize}
+  \item Move around with the breadcrumb trail, the \code{..} entry or \ui{Go to path}.
+  \item Upload files; download one or many to a folder you choose.
+  \item Rename, delete (it asks first), make folders, refresh.
+  \item \iStar{} bookmarks the current folder, per profile.
+  \item Ctrl-click (\ph{E1C4}-click) or Shift-click to select several things. Transfers show progress as they go.
+\end{itemize}
+
+\section{Drag and drop}
+
+Drop files onto a terminal and choose:
+
+\begin{description}
+  \item[Upload to current directory] Pick the remote folder (SSH only).
+  \item[Paste contents] Types the file's contents into the terminal, as if you'd typed it.
+\end{description}
+
+The upload picker looks like the SFTP browser but shows folders only, labelled \proto[amber]{READ ONLY} if you can't
+write there and \proto[rose]{NO READ} if you can't look inside. Keyboard fans: \kbd{↑}\kbd{↓} to move, \kbd{Enter} to
+choose, \kbd{Backspace} to go up, \kbd{Esc} to cancel. If the SFTP browser is open, the picker starts in the same folder.
+
+% =========================================================================================
+\chapter{Port forwards}\label{ch:forwards}
+\chapmeta{3 minutes}{You'll reach a database or web app that only listens on the server}
+
+\begin{tldr}
+\emph{Local} forwards bring a remote port to your machine. \emph{Remote} forwards do the opposite.
+\end{tldr}
+
+Forwards saved in an SSH profile (under \ui{Port Forwarding}, with \ui{Active} ticked) start when you connect.
+To manage them on a live session, right-click the terminal\then\ui{Port Forwards}, or \menu{Session\then Port forwards}.
+
+\begin{description}
+  \item[Local \iArrow] Listen on your computer, forward to somewhere the server can reach.
+        Example: \code{127.0.0.1:15432}\then\code{127.0.0.1:5432} lets your desktop database app talk to Postgres on
+        the server as if it were local.
+  \item[Remote \ph{E058}] Ask the server to listen and send connections back to somewhere \emph{your} computer can reach.
+        Great for showing a colleague the dev server running on your laptop.
+\end{description}
+
+Active forwards are listed with an \proto[accent]{L} or \proto[violet]{R} badge and a stop button. Toasts tell you when one
+starts, stops or fails.
+
+% =========================================================================================
+\chapter{Recordings}\label{ch:recordings}
+\chapmeta{2 minutes}{You'll have a replayable record of exactly what happened}
+
+\keys{\mod+Shift+R} starts and stops recording the active session. A red dot appears on the tab and \ui{REC} in
+the status bar. Recordings are standard asciicast v2 files, so other tools (like \code{asciinema}) can play them too.
+
+\crop{recordings.png}{712}{392}{690}{415}{0.75\linewidth}{The recordings browser. Play, delete, or tidy up in bulk.}
+
+The browser (sidebar footer, \menu{Session} menu or palette) shows how many recordings you have and how much space
+they take. Play or delete each one, or use \ui{Clean up} to remove recordings older than 7, 30 or 90 days, or to keep
+the total under 1\,GB or 5\,GB. Playback has play/pause, restart, a seek bar and speed control.
+
+\begin{protip}
+Record the next time you do something fiddly and rare (a database failover, a certificate rotation). Six months
+later, ``how did we do that again?'' has an answer you can literally watch.
+\end{protip}

docs/guide/chapters/part4-safe.tex

@@ -0,0 +1,139 @@
+\guidepart{amber}{Stay safe}{Stay safe}
+  {Passwords, keys and host checks, minus the jargon headache.}
+  {\partitem{\iLock}{Passwords and the vault}
+   \partitem{\iShield}{Host keys: is it really that server?}
+   \partitem{\iKey}{SSH keys}}
+
+% =========================================================================================
+\chapter{Passwords and the vault}\label{ch:secrets}
+\chapmeta{5 minutes}{You'll know exactly where your passwords live and who can read them}
+
+\begin{tldr}
+Passwords go in your OS keychain. If there isn't one, they go in an encrypted vault protected by a master password.
+For each password you choose: save it, remember it until you quit, or ask every time.
+\end{tldr}
+
+\section{Where secrets live}
+
+\begin{center}
+\begin{tikzpicture}[
+  box/.style={rounded corners=6pt, fill=#1!12, draw=#1!60, line width=0.6pt, minimum height=13mm, text width=40mm,
+    align=center, font=\small},
+  arr/.style={-latex, line width=0.8pt, color=muted}]
+  \node[box=accent] (need) {\heavy A session needs\\a password};
+  \node[box=green, right=12mm of need] (kc) {\heavy OS keychain\\{\footnotesize Keychain · Credential Manager · Secret Service}};
+  \node[box=amber, right=12mm of kc] (vault) {\heavy Encrypted vault\\{\footnotesize AES-256-GCM, Argon2id}};
+  \node[box=rose, below=9mm of kc] (ask) {\heavy Ask you\\{\footnotesize then carry on}};
+  \draw[arr] (need) -- (kc);
+  \draw[arr] (kc) -- node[above, font=\scriptsize]{not there?} (vault);
+  \draw[arr] (vault) |- node[pos=0.25, right, font=\scriptsize]{still not there?} (ask);
+\end{tikzpicture}
+\end{center}
+
+\begin{description}
+  \item[OS keychain first] macOS Keychain, Windows Credential Manager, or the Linux Secret Service (GNOME Keyring,
+        KWallet and friends).
+  \item[Encrypted vault as backup] If there's no keychain, or it refuses, secrets go into Nexus Terminal's own
+        vault: AES-256-GCM with a key derived from your master password by Argon2id using 128\,MiB of memory. In
+        plain English: very, very expensive to brute-force.
+\end{description}
+
+\section{Setting up the vault}
+
+\menu{Settings\then Security\then Initialise Secret Store}. Choose a master password; the strength meter goes from
+\proto[rose]{Weak} through \proto[amber]{Fair} and \proto[accent]{Good} to \proto[green]{Strong}. Unlock and lock it
+from the same page, from the palette, or by clicking the vault badge in the status bar. It locks itself when you quit.
+
+\crop{settings-security.png}{581}{253}{576}{285}{0.8\linewidth}{Security settings on a machine without an OS keychain: the vault does the job instead.}
+
+\begin{danger}[There's no ``forgot password'' link]
+Lose the master password and the secrets in the vault are gone for good. That's the point of encryption. Put it in
+your password manager.
+\end{danger}
+
+\section{Three ways to handle each password}
+
+Every password, passphrase, token or TOTP secret has its own setting:
+
+\begin{center}
+\begin{tabular}{@{}p{0.3\linewidth}p{0.3\linewidth}p{0.3\linewidth}@{}}
+  \begin{tcolorbox}[colback=green!8, boxrule=0pt, arc=6pt, fontupper=\small, height=33mm]
+    {\heavy\color{green!60!black}\iLock\ Save securely}\par\smallskip Stored in the keychain or vault and used automatically. Most convenient.
+  \end{tcolorbox} &
+  \begin{tcolorbox}[colback=accent!8, boxrule=0pt, arc=6pt, fontupper=\small, height=33mm]
+    {\heavy\color{accent!80!black}\iClock\ Remember for this session}\par\smallskip Asked once, kept in memory, never written to disk.
+  \end{tcolorbox} &
+  \begin{tcolorbox}[colback=amber!10, boxrule=0pt, arc=6pt, fontupper=\small, height=33mm]
+    {\heavy\color{amber!75!black}\iDetective\ Ask every time}\par\smallskip Asked on every single connection. Most paranoid.
+  \end{tcolorbox}
+\end{tabular}
+\end{center}
+
+When Nexus Terminal needs a secret it doesn't have, it asks. Press \kbd{Esc} or \ui{Cancel} to give up on that
+connection.
+
+\section{Seeing and changing what's saved}
+
+\ui{Stored credentials} on the Security page lists every saved password, passphrase and token by profile, and whether
+it's in the keychain or the vault. \ui{Forget} deletes one. \ui{Change Master Password…} re-encrypts the whole vault
+under a new password in one go.
+
+\begin{sidequest}[What gets written down?]
+Connections, disconnections, profile changes, credential access, imports and exports go into an audit log in the
+database. Secrets themselves never do. TOTP secrets live in the keychain or vault too, never in the profile.
+\end{sidequest}
+
+% =========================================================================================
+\chapter{Host keys: is it really that server?}\label{ch:hostkeys}
+\chapmeta{3 minutes}{You'll understand the scary fingerprint dialog and what to do about it}
+
+\begin{tldr}
+Every SSH server (and every RDP server, via its certificate) has a fingerprint. Nexus Terminal remembers it the first time and shouts if it ever changes.
+A changed fingerprint means a reinstalled server, or someone in the middle. Find out which before carrying on.
+\end{tldr}
+
+Pick a policy per SSH profile under \ui{Host Verification}:
+
+\renewcommand\arraystretch{1.5}
+\begin{tabularx}{\linewidth}{@{}>{\leavevmode\heavy\color{ink}}p{48mm}X@{}}
+  \toprule
+  Strict (known hosts only)   & Only connects to servers you've already trusted.\\
+  Ask on new or changed keys  & Shows the fingerprint and asks. New: \ui{Accept \& Save} or \ui{Reject}. Changed:
+                                \ui{Reject}, \ui{Accept Once} or \ui{Accept \& Update}. The default.\\
+  Accept new, reject changed  & Trusts first-time servers silently, still refuses changed keys.\\
+  Insecure (accept anything)  & Exactly what it says. Lab use only.\\
+  \bottomrule
+\end{tabularx}
+
+Under \emph{Strict} and \emph{Accept new}, a key that differs from the saved one is rejected outright.
+
+\crop{settings-knownhosts.png}{581}{253}{576}{285}{0.8\linewidth}{Known hosts. Click a fingerprint to copy it; \ui{Remove} to forget a server.}
+
+\begin{quickwin}
+Nexus Terminal keeps its own list, but \ui{Import \textasciitilde/.ssh/known\_hosts} brings in everything your
+command-line \code{ssh} already trusts (hashed names can't be read back, so those are skipped). \ui{Export…} goes the
+other way, in OpenSSH format.
+\end{quickwin}
+
+\section{Certificate authorities}
+
+Big estates sign host keys with an SSH certificate authority instead of handing out fingerprints. \ui{Trust a CA…}
+adds the CA's public key for a host pattern in OpenSSH style (\code{*.corp.example}, \code{[jump.example]:2222},
+\code{!old.corp.example}); \code{@cert-authority} lines in an imported \code{known\_hosts} do the same. A server the CA
+covers must then show a certificate the CA signed, naming that host and in date. It's trusted without a prompt, and
+anything else is refused.
+
+% =========================================================================================
+\chapter{SSH keys}\label{ch:keys}
+\chapmeta{2 minutes}{You'll have a key pair without memorising ssh-keygen flags}
+
+\menu{Session\then SSH key manager} (or the palette) lists the key pairs in \code{\textasciitilde/.ssh} with their type. Copy a
+public key to the clipboard (ready to paste into GitHub or \code{authorized\_keys}), delete a pair, or generate a new
+\proto[teal]{Ed25519}, \proto[accent]{RSA} (2048 or 4096 bits) or \proto[violet]{ECDSA} key with an optional passphrase.
+
+\crop{keys.png}{725}{523}{725}{546}{0.75\linewidth}{The SSH key manager.}
+
+\begin{protip}
+Not sure which type? Pick Ed25519. It's small, fast and secure. Keys are generated inside Nexus Terminal and
+saved in the usual OpenSSH format, so \code{ssh} and \code{git} can use them too.
+\end{protip}

docs/guide/chapters/part5-yours.tex

@@ -0,0 +1,123 @@
+\guidepart{pink}{Make it yours}{Make it yours}
+  {Settings, backups, and keeping several computers in step.}
+  {\partitem{\iGear}{Settings}
+   \partitem{\iUpload}{Import and export}
+   \partitem{\iPlane}{Moving house}}
+
+% =========================================================================================
+\chapter{Settings}\label{ch:settings}
+\chapmeta{3 minutes}{You'll know where every setting lives}
+
+\keys{\mod+,} opens settings (also the \iGear{} in the sidebar footer and \menu{File\then Settings}). Change things,
+then click \ui{Save}.
+
+\begin{center}\begin{minipage}[t]{0.49\linewidth}\crop{settings-general.png}{581}{253}{576}{285}{\linewidth}{General}\end{minipage}\hfill\begin{minipage}[t]{0.49\linewidth}\crop{settings-terminal.png}{581}{253}{576}{285}{\linewidth}{Terminal}\end{minipage}\end{center}
+
+\begin{description}
+  \item[General] App theme (Pro, Midnight, Light), default protocol for new profiles, \ui{Restore tabs at launch}
+        (saved connections reconnect, local shells reopen in the folder they were in), whether to ask before closing or
+        disconnecting, whether remote programs may write to your clipboard, a confirmation before pasting several lines,
+        the update check, status bar, sidebar width, and the local shell (empty for the system default, or
+        \ui{Browse…}).
+  \item[Terminal] Colour scheme, font, size, scrollback and cursor style. These are the defaults for new profiles;
+        each profile can override them.
+  \item[Security] Keychain and vault status; set up, unlock or lock the vault; change the master password; your
+        stored credentials; profile sync.
+  \item[Known Hosts] Saved server fingerprints, with first-seen and last-seen times; import and export
+        \code{known\_hosts}; trusted SSH certificate authorities.
+  \item[Diagnostics] Version, platform, where your data and log live, and the state of the keychain, vault and sync.
+        \ui{Copy Diagnostics} for bug reports (never includes credentials).
+  \item[Help] Built-in help: connection types, shortcuts and troubleshooting, when this guide isn't to hand.
+  \item[About] Version, \ui{Check for Updates} and \ui{Import \textasciitilde/.ssh/config}.
+\end{description}
+
+\crop{settings-diagnostics.png}{604}{600}{604}{20}{0.8\linewidth}{Diagnostics: everything a bug report needs, nothing secret.}
+
+\section{Updates}
+
+Nexus Terminal checks once at launch. If there's a newer version the status bar says \ui{Update available}; click it to
+see the release notes and a \ui{View release} button. Nothing downloads or installs behind your back.
+
+% =========================================================================================
+\chapter{Import and export}\label{ch:transfer}
+\chapmeta{3 minutes}{You'll back up your profiles, or copy them to another computer}
+
+\begin{tldr}
+\menu{File\then Export profiles…} makes a password-protected \code{.nexus} file. \menu{File\then Import profiles…}
+reads it back. Already have an \code{\textasciitilde/.ssh/config}? Import that too.
+\end{tldr}
+
+\begin{description}
+  \item[Encrypted export] Choose the profiles, set a password, save a \code{.nexus} file. Saved passwords aren't
+        included, so the file is safe to email to yourself.
+  \item[Encrypted import] Pick a \code{.nexus} file, enter its password and decide what happens to
+        profiles that already exist: \ui{Skip existing}, \ui{Overwrite existing} or \ui{Create duplicates}.
+  \item[JSON] \ui{Export Profiles (JSON)} and \ui{Import Profiles (JSON)} are in the palette. Tick
+        \ui{Include secrets} to keep passwords typed by login scripts, which are otherwise blanked. Proxy passwords and
+        TOTP secrets live in the keychain or vault, so no export carries them.
+  \item[OpenSSH config] \menu{File\then Import \textasciitilde/.ssh/config} turns your \code{Host} blocks into profiles,
+        with host names, users, ports, identity files and jump hosts.
+\end{description}
+
+\crop{export.png}{906}{388}{904}{390}{0.55\linewidth}{Exporting profiles. Everything's ticked to start with; untick what you don't want.}
+
+\begin{danger}[JSON with secrets is not encrypted]
+A JSON export with \ui{Include secrets} ticked has those login-script passwords in plain text. Use the encrypted \code{.nexus} export to
+move things between machines.
+\end{danger}
+
+% =========================================================================================
+\chapter{Moving house}\label{ch:move}
+\chapmeta{3 minutes}{Your connections will follow you from laptop to desktop to work machine}
+
+\begin{tldr}
+Pick a folder every machine can see, set the same sync password on each, done. Profiles stay in step; passwords
+stay put on each machine.
+\end{tldr}
+
+\section{Profile sync}
+
+\menu{Settings\then Security\then Profile sync}. \ui{Choose…} a folder your machines share (Dropbox, iCloud Drive,
+OneDrive, Nextcloud, a network share, or a git checkout you commit) and set the same \ui{Sync password} everywhere.
+Nexus Terminal keeps one encrypted file there, \code{nexus-profiles.nexus}, and merges it at launch, a few seconds
+after you change a profile, every ten minutes and whenever you click \ui{Sync Now}.
+
+\begin{checklist}
+  \item[\color{green}\iCheck] Edited on two machines? The newer change wins, profile by profile.
+  \item[\color{green}\iCheck] Deleted on one machine? It goes from the others too (unless someone edited it afterwards).
+  \item[\color{rose}\ph{E4F6}] Passwords, keys and tokens never sync. Each machine keeps its own in its keychain or vault.
+\end{checklist}
+
+\crop{settings-security.png}{581}{253}{576}{285}{0.8\linewidth}{Profile sync lives on the Security page, under your stored credentials.}
+
+\begin{headsup}
+Lose the sync password and the sync file can't be read, just like an encrypted export. Your local profiles are
+fine.
+\end{headsup}
+
+\section{One-off moves}
+
+Not worth setting up sync? \menu{File\then Export profiles…} on the old machine, \menu{File\then Import profiles…}
+on the new one (see \hyperref[ch:transfer]{Import and export}). Known hosts travel the same way through
+\ui{Export…} and \ui{Import} on the Known Hosts page.
+
+\section{Where everything lives}
+
+\renewcommand\arraystretch{1.45}
+\begin{tabularx}{\linewidth}{@{}>{\leavevmode\heavy\color{ink}}p{20mm}X@{}}
+  \toprule
+  macOS   & \code{\textasciitilde/Library/Application Support/NexusTerminal}\\
+  Windows & \code{\%APPDATA\%\textbackslash NexusTerminal}\\
+  Linux   & \code{\$XDG\_CONFIG\_HOME/NexusTerminal}, usually \code{\textasciitilde/.config/NexusTerminal}\\
+  \bottomrule
+\end{tabularx}
+
+Inside: \code{nexus.db} (profiles, known hosts, preferences, snippets, IRC state and the audit log),
+\code{vault/vault.json}, \code{recordings/}, \code{triggers.json}, \code{sftp-bookmarks.json} and \code{nexus.log}, the
+diagnostic log. Keychain entries are
+stored under the service name \code{NexusTerminal}.
+
+\begin{protip}[Try things without touching your real data]
+Start Nexus Terminal with \code{--data-dir /some/other/folder} and it uses that folder instead. Brilliant for
+experiments, demos and a portable install on a USB stick.
+\end{protip}

docs/guide/chapters/part6-fix.tex

@@ -0,0 +1,106 @@
+\guidepart{rose}{Fix it}{When things go wrong}
+  {Symptom first, fix second. No essays.}
+  {\partitem{\iLifebuoy}{Troubleshooting, by symptom}}
+\label{part:fix}
+
+% =========================================================================================
+\chapter{Troubleshooting, by symptom}\label{ch:trouble}
+\chapmeta{as long as it takes}{You'll find your symptom and the fix in one place}
+
+\begin{tldr}
+Find the heading that matches what you're seeing. Try the fixes in order. Most problems are the network, the
+password, or the baud rate.
+\end{tldr}
+
+\section{Connecting}
+
+\fix{``Authentication failed''}{%
+\begin{itemize}
+  \item Check the username, password, key path and the ticked \ui{Auth Methods}.
+  \item If the key has a passphrase, check how the passphrase is stored (\ui{Passphrase Mode}).
+  \item Two-factor server? Click \ui{Test} next to the TOTP secret and compare with your phone. Check your clock.
+  \item Saved password not being used? The vault might be locked: click \ui{Vault locked} in the status bar.
+\end{itemize}}
+
+\fix{``Host key verification failed''}{%
+The server's fingerprint changed since you last connected. That happens when a server is rebuilt, but it's also exactly
+what an attack looks like. \textbf{Check with whoever runs the server.} If it's legitimate:
+choose \ui{Accept \& Update} in the warning (or \ui{Accept Once} to defer the decision). Under a Strict or Accept-new
+policy there's no prompt: \menu{Settings\then Known Hosts}, \ui{Remove} the entry and reconnect.}
+
+\fix{It just says ``Connecting…'' forever}{%
+\begin{itemize}
+  \item Click \ui{Test} in the profile editor. If that fails too, it's the network, a firewall or the wrong port.
+  \item Behind a corporate proxy? Set one up under \ui{Proxy} (SSH profiles).
+  \item Going through a bastion? Check each jump host on its own first.
+\end{itemize}}
+
+\fix{The session keeps reconnecting}{%
+Check the network and the credentials, then the profile's auto-reconnect settings. Reconnection backs off (1\,s, 2\,s,
+4\,s… up to 30\,s) and stops after the maximum number of attempts.}
+
+\section{Serial}
+
+\fix{The port won't open}{%
+\begin{itemize}
+  \item Is the adapter plugged in? Hit refresh in the device list.
+  \item \textbf{Permission denied} on Linux: add yourself to \code{dialout} (or \code{uucp}), then log out and back in.
+  \item On a Mac, use \code{/dev/cu.*}, not \code{/dev/tty.*}.
+  \item \textbf{Port is in use by another program}: close \code{screen}, \code{minicom}, the Arduino IDE serial monitor or
+        whatever else has it open.
+\end{itemize}}
+
+\fix{Gibberish on screen}{The baud rate, parity or stop bits don't match the device. Check its manual.}
+
+\section{Remote desktops}
+
+\fix{VNC won't connect}{%
+\begin{itemize}
+  \item VNC ports are 5900 plus the display number: \code{:0} is 5900, \code{:1} is 5901.
+  \item Check the password and how it's stored.
+  \item Using an SSH tunnel? Check the tunnel's host, user, login method and key, and the host key policy.
+  \item Connecting to a Mac? Turn on password access in macOS Screen Sharing settings (see p.\,\pageref{ch:vnc}).
+\end{itemize}}
+
+\fix{RDP won't connect}{%
+\begin{itemize}
+  \item Linux box running xrdp? Tick \ui{Allow servers without NLA}.
+  \item ``Logon failed''? Check the domain. Kerberos users: the KDC must be reachable directly, not through the proxy.
+  \item Certificate warning after a server rebuild? That's expected once; compare the fingerprint, then
+        \ui{Accept \& Update}.
+  \item Going through an RD Gateway? It needs a certificate from a public CA and Basic authentication over HTTPS.
+\end{itemize}}
+
+\section{Files}
+
+\fix{Upload is greyed out or fails}{%
+The folder is probably \proto[amber]{READ ONLY} for your user. Pick another, or check permissions on the server. Uploads
+need an SSH session; other protocols can't do it.}
+
+\fix{``NO READ'' on a folder}{You don't have permission to look inside. Try the parent folder, or ask the server's admin.}
+
+\section{The terminal itself}
+
+\fix{The terminal is the wrong size}{%
+Resize the window or nudge a split divider; the terminal re-fits itself. Still wrong? Reconnect. Very old servers may
+prefer a different \ui{Terminal Type} in the profile (try \code{vt100}).}
+
+\fix{The scroll wheel moves the cursor instead of scrolling}{%
+You're in a full-screen program (\code{less}, \code{vim}, \code{tmux}). That's how terminals work: the wheel sends arrow keys
+there. Quit the program, or use its own scrolling (in \code{tmux}: \keys{Ctrl+B} then \kbd{[}).}
+
+\fix{Emoji are in black and white}{Known limitation: colour emoji show as monochrome glyphs. Everything else renders
+normally.}
+
+\begin{quickwin}[Still stuck?]
+Start Nexus Terminal with \code{--data-dir} pointing at an empty folder and try the same connection there. If it
+works, something in your profile is off; duplicate the working one and compare.
+\end{quickwin}
+
+\section{Still stuck?}
+
+\fix{Something odd that isn't on this list}{%
+Look at \code{nexus.log} in your data folder (\menu{Settings\then Diagnostics} shows where): connections, reconnects,
+host-key checks and errors, never passwords or what's on screen. Start Nexus Terminal with \code{RUST\_LOG=debug} for
+more detail. Reporting a bug? \ui{Copy Diagnostics} and paste it in.}
+

docs/guide/fonts/Phosphor-LICENSE.txt

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2023 Romet Tagobert
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

docs/guide/nexus-guide.sty

@@ -0,0 +1,286 @@
+% Nexus Terminal user guide — look and feel. Build with lualatex (see Makefile).
+\NeedsTeXFormat{LaTeX2e}
+\ProvidesPackage{nexus-guide}
+
+\RequirePackage[a4paper,top=24mm,bottom=26mm,inner=22mm,outer=26mm,headsep=8mm,footskip=12mm]{geometry}
+% Latin Modern OpenType isn't always installed, and the kernel selects it once before the guide's own
+% fonts take over. Point that one use at Inter so the build only needs fonts from the repo.
+\DeclareFontShape{TU}{lmr}{m}{n}{<->"[../../rust/app/assets/fonts/Inter-Regular.ttf]:mode=node;"}{}
+\RequirePackage{fontspec}
+\RequirePackage[dvipsnames]{xcolor}
+\RequirePackage{graphicx}
+\RequirePackage[most]{tcolorbox}
+\RequirePackage{tikz}
+\usetikzlibrary{calc,positioning,shadows.blur,fadings}
+\RequirePackage{titlesec}
+\RequirePackage{fancyhdr}
+\RequirePackage{enumitem}
+\RequirePackage{tabularx}
+\RequirePackage{booktabs}
+\RequirePackage{multicol}
+\RequirePackage{eso-pic}
+\RequirePackage{etoolbox}
+\RequirePackage{needspace}
+\RequirePackage{microtype}
+\RequirePackage[hidelinks]{hyperref}
+\RequirePackage{bookmark}
+
+% --- Fonts: the app's own Inter + JetBrains Mono, and its Phosphor icons ----------------
+\defaultfontfeatures{Ligatures=TeX}
+\setmainfont{Inter-Regular.ttf}[
+  Path=../../rust/app/assets/fonts/,
+  BoldFont=Inter-SemiBold.ttf,
+  ItalicFont=Inter-Regular.ttf, ItalicFeatures={FakeSlant=0.18},
+  BoldItalicFont=Inter-SemiBold.ttf, BoldItalicFeatures={FakeSlant=0.18}]
+\setsansfont{Inter-Regular.ttf}[Path=../../rust/app/assets/fonts/, BoldFont=Inter-SemiBold.ttf]
+\setmonofont{JetBrainsMono-Regular.ttf}[Path=../../rust/app/assets/fonts/, Scale=0.92]
+\newfontfamily\heavy{Inter-SemiBold.ttf}[Path=../../rust/app/assets/fonts/]
+\newfontfamily\phfont{Phosphor.ttf}[Path=fonts/]
+\newfontfamily\phfill{Phosphor-Fill.ttf}[Path=fonts/]
+\linespread{1.18}
+\setlength{\parindent}{0pt}
+\setlength{\parskip}{0.62em}
+\raggedbottom
+\sloppy
+
+% --- Palette (mirrors the app's Pro theme) ---------------------------------------------
+\definecolor{ink}{HTML}{1B1B1F}
+\definecolor{ink2}{HTML}{26262C}
+\definecolor{body}{HTML}{2A2A33}
+\definecolor{muted}{HTML}{6B6B78}
+\definecolor{rule}{HTML}{E4E4EA}
+\definecolor{paper}{HTML}{F7F7FA}
+\definecolor{accent}{HTML}{3B82F6}
+\definecolor{teal}{HTML}{14B8A6}
+\definecolor{violet}{HTML}{8B5CF6}
+\definecolor{amber}{HTML}{F59E0B}
+\definecolor{rose}{HTML}{F43F5E}
+\definecolor{pink}{HTML}{EC4899}
+\definecolor{green}{HTML}{22C55E}
+\definecolor{slate}{HTML}{64748B}
+\color{body}
+
+% Page-level drawing. Everything that paints relative to the page goes through here, drawn at shipout
+% from the page's lower-left corner, so it never depends on remember-picture positions settling.
+% Inside, the node (pg) is the whole page: use pg.north west, pg.south east and so on.
+\newcommand\pgnode{\node[inner sep=0pt, minimum width=\paperwidth, minimum height=\paperheight, anchor=south west] (pg) at (0,0) {};}
+\newcommand\pagecanvas[1]{\AddToShipoutPictureBG*{\AtPageLowerLeft{\begin{tikzpicture}[overlay]\pgnode#1\end{tikzpicture}}}}
+
+% Current part colour (set by \guidepart).
+\colorlet{partcol}{accent}
+\newcounter{guidepart}
+\newcommand\partshort{}
+
+% --- Icons ------------------------------------------------------------------------------
+\newcommand\ph[1]{{\phfont\symbol{"#1}}}
+\newcommand\phf[1]{{\phfill\symbol{"#1}}}
+\newcommand\iTerminal{\ph{EAE8}}  \newcommand\iBolt{\ph{E2DE}}     \newcommand\iBrain{\ph{E74E}}
+\newcommand\iWarn{\ph{E4E0}}      \newcommand\iBulb{\ph{E2DC}}     \newcommand\iCoffee{\ph{E1C2}}
+\newcommand\iRocket{\ph{E3FE}}    \newcommand\iCheck{\ph{E184}}    \newcommand\iTimer{\ph{E492}}
+\newcommand\iKeyboard{\ph{E2D8}}  \newcommand\iSparkle{\ph{E6A2}}  \newcommand\iShield{\ph{E40C}}
+\newcommand\iWand{\ph{E6B6}}      \newcommand\iBug{\ph{E5F4}}      \newcommand\iStar{\phf{E46A}}
+\newcommand\iSiren{\ph{E9B8}}     \newcommand\iWave{\ph{E580}}     \newcommand\iTarget{\ph{E47C}}
+\newcommand\iMap{\ph{E31A}}       \newcommand\iList{\ph{EADC}}     \newcommand\iBox{\ph{E45E}}
+\newcommand\iKey{\ph{E2D6}}       \newcommand\iPlugs{\ph{EB5A}}    \newcommand\iFolder{\ph{E256}}
+\newcommand\iBroadcast{\ph{E0F2}} \newcommand\iFilm{\ph{E792}}     \newcommand\iCode{\ph{E1BC}}
+\newcommand\iGear{\ph{E270}}      \newcommand\iLock{\ph{E2FA}}     \newcommand\iGithub{\ph{E576}}
+\newcommand\iChat{\ph{E16C}}      \newcommand\iDesktop{\ph{E560}}  \newcommand\iUsb{\ph{E956}}
+\newcommand\iTree{\ph{E67C}}      \newcommand\iArrows{\ph{E0A0}}   \newcommand\iCmd{\ph{E1C4}}
+\newcommand\iSearch{\ph{E30C}}    \newcommand\iSplit{\ph{E870}}    \newcommand\iLifebuoy{\ph{E63A}}
+\newcommand\iInfo{\ph{E2CE}}      \newcommand\iPin{\ph{E3E2}}      \newcommand\iConfetti{\ph{E81A}}
+\newcommand\iDetective{\ph{E83E}} \newcommand\iCompass{\ph{E1C8}}  \newcommand\iBinary{\ph{EE60}}
+\newcommand\iPalette{\ph{E6C8}}   \newcommand\iRecord{\ph{E3EE}}   \newcommand\iArrow{\ph{E06C}}
+\newcommand\iClock{\ph{E19A}}     \newcommand\iFlag{\ph{EA38}}     \newcommand\iPlug{\ph{E946}}
+\newcommand\iGhost{\ph{E62A}}     \newcommand\iBell{\ph{E5E8}}     \newcommand\iHourglass{\ph{E2B2}}
+\newcommand\iDownload{\ph{E20C}}  \newcommand\iUpload{\ph{E4C0}}   \newcommand\iPlane{\ph{E398}}
+
+% --- Inline bits --------------------------------------------------------------------------
+% \kbd{Ctrl} — a keycap. \keys{Ctrl+Shift+K} — keycaps joined with thin pluses.
+\newtcbox{\kbd}{on line, boxrule=0.4pt, arc=2.2pt, colback=paper, colframe=rule!70!slate,
+  boxsep=0pt, left=3.2pt, right=3.2pt, top=1.6pt, bottom=1.2pt, fontupper=\ttfamily\footnotesize\color{ink}}
+% \mod is "Ctrl, or ⌘ on a Mac": every shortcut in the guide is written \keys{\mod+K}.
+\renewcommand\mod{\kbd{Ctrl\,/\,\ph{E1C4}}}
+\def\keystop{\relax}\def\modtok{\mod}
+\DeclareRobustCommand\keys[1]{\keysplit#1+\relax+}
+\def\keysplit#1+{\def\kk{#1}\ifx\kk\keystop\else\keycap{#1}\expandafter\keysplitnext\fi}
+\def\keysplitnext#1+{\def\kk{#1}\ifx\kk\keystop\else{\kern0.15em\scriptsize\color{muted}+\kern0.15em}\keycap{#1}\expandafter\keysplitnext\fi}
+\newcommand\keycap[1]{\def\kc{#1}\ifx\kc\modtok\mod\else\kbd{#1}\fi}
+
+\newcommand\ui[1]{{\heavy\color{ink}#1}}               % on-screen labels
+\newcommand\code[1]{{\ttfamily\color{ink}#1}}           % file paths and commands
+\newcommand\menu[1]{{\heavy\color{ink}#1}}              % File → Thing
+\newcommand\then{\,{\color{muted}\iArrow}\,}
+\newcommand\proto[2][accent]{\tcbox[on line, arc=6pt, boxrule=0pt, colback=#1!14, boxsep=0pt,
+  left=4pt, right=4pt, top=1.2pt, bottom=1.2pt]{\scriptsize\heavy\color{#1!80!black}#2}}
+
+% --- Callout boxes ----------------------------------------------------------------------
+\tcbset{guidebox/.style={enhanced, breakable, arc=7pt, boxrule=0pt, left=12pt, right=12pt,
+  top=8pt, bottom=8pt, before skip=10pt, after skip=12pt, fontupper=\small,
+  parbox=false, before upper={\setlength{\parskip}{0.5em}}}}
+\newcommand\boxhead[3]{{\heavy\color{#1}\large#2\enspace\normalsize#3}\par\vspace{2pt}}
+
+\newtcolorbox{tldr}{guidebox, colback=partcol!8, borderline west={3pt}{0pt}{partcol},
+  before upper={\boxhead{partcol}{\iBolt}{TL;DR}\setlength{\parskip}{0.4em}}}
+\newtcolorbox{quickwin}[1][Quick win]{guidebox, colback=green!8, borderline west={3pt}{0pt}{green},
+  before upper={\boxhead{green!65!black}{\iTarget}{#1}}}
+\newtcolorbox{headsup}[1][Heads up]{guidebox, colback=amber!10, borderline west={3pt}{0pt}{amber},
+  before upper={\boxhead{amber!75!black}{\iWarn}{#1}}}
+\newtcolorbox{protip}[1][Pro tip]{guidebox, colback=accent!7, borderline west={3pt}{0pt}{accent},
+  before upper={\boxhead{accent!80!black}{\iBulb}{#1}}}
+\newtcolorbox{sidequest}[1][Side quest]{guidebox, colback=violet!7,
+  borderline west={3pt}{0pt}{violet}, borderline={0.5pt}{0pt}{violet!35,dashed},
+  before upper={\boxhead{violet}{\iCompass}{#1 {\normalfont\footnotesize\color{muted}\enspace·\enspace optional, skip it if you're in a hurry}}}}
+\newtcolorbox{danger}[1][Careful]{guidebox, colback=rose!8, borderline west={3pt}{0pt}{rose},
+  before upper={\boxhead{rose!85!black}{\iSiren}{#1}}}
+
+% "You are here": a one-line chapter header strip with reading time.
+\newcommand\chapmeta[2]{%
+  \begin{tcolorbox}[enhanced, arc=6pt, boxrule=0pt, colback=paper, left=10pt, right=10pt,
+    top=5pt, bottom=5pt, before skip=0pt, after skip=10pt, fontupper=\small\color{muted}]
+  {\color{partcol}\iTimer}\enspace about \textbf{#1}\hfill{\color{partcol}\iTarget}\enspace #2
+  \end{tcolorbox}}
+
+% Checklists.
+\newlist{checklist}{itemize}{1}
+\setlist[checklist]{label={\color{partcol}\large\iBox}, leftmargin=1.9em, itemsep=2pt, topsep=4pt}
+\setlist[itemize]{label={\color{partcol}\small\textbullet}, leftmargin=1.4em, itemsep=1pt, topsep=3pt}
+\setlist[enumerate]{label={\heavy\color{partcol}\arabic*}, leftmargin=1.6em, itemsep=2pt, topsep=4pt}
+\setlist[description]{font=\heavy\color{ink}, leftmargin=1.2em, itemsep=2pt}
+
+% --- Screenshots --------------------------------------------------------------------------
+% \shot[width]{file}{caption}
+\newcommand\shot[3][\linewidth]{%
+  \par\needspace{0.3\textheight}\begin{center}
+  \begin{tikzpicture}
+    \node[inner sep=0pt, rounded corners=6pt, blur shadow={shadow blur steps=8, shadow xshift=0pt,
+      shadow yshift=-2pt, shadow opacity=25}] (img) {\includegraphics[width=#1]{img/#2}};
+    \draw[rule!60!slate, line width=0.4pt, rounded corners=3pt] (img.south west) rectangle (img.north east);
+  \end{tikzpicture}\par\vspace{4pt}
+  {\footnotesize\color{muted}#3}\end{center}\vspace{-4pt}}
+
+% Two screenshots side by side.
+\newcommand\shotpair[4]{%
+  \par\needspace{0.22\textheight}\begin{center}
+  \begin{minipage}[t]{0.485\linewidth}\centering\includegraphics[width=\linewidth]{img/#1}\par\vspace{3pt}{\footnotesize\color{muted}#2}\end{minipage}\hfill
+  \begin{minipage}[t]{0.485\linewidth}\centering\includegraphics[width=\linewidth]{img/#3}\par\vspace{3pt}{\footnotesize\color{muted}#4}\end{minipage}
+  \end{center}}
+
+% A crop of a screenshot: \crop{file}{left}{bottom}{right}{top}{width}{caption}, trims in px of the 2720x1720 image.
+\newcommand\crop[7]{%
+  \par\needspace{0.2\textheight}\begin{center}
+  \begin{tikzpicture}
+    \node[inner sep=0pt, blur shadow={shadow blur steps=8, shadow yshift=-2pt, shadow opacity=25}] (img)
+      {\includegraphics[width=#6, trim=#2 #3 #4 #5, clip]{img/#1}};
+    \draw[rule!60!slate, line width=0.4pt] (img.south west) rectangle (img.north east);
+  \end{tikzpicture}\par\vspace{4pt}{\footnotesize\color{muted}#7}\end{center}\vspace{-4pt}}
+
+% Annotated screenshot: \begin{annotated}{file} \callout{1}{x}{y} … \end{annotated}, x/y in 0–1 from top left.
+\newenvironment{annotated}[1]{%
+  \par\begin{center}\begin{tikzpicture}
+  \node[anchor=north west, inner sep=0pt, blur shadow={shadow blur steps=8, shadow yshift=-2pt, shadow opacity=25}] (img)
+    {\includegraphics[width=\linewidth]{img/#1}};
+  \draw[rule!60!slate, line width=0.4pt] (img.south west) rectangle (img.north east);
+  \begin{scope}[x={(img.north east)}, y={($(img.north west)-(img.south west)$)}, shift={(img.north west)}]}
+  {\end{scope}\end{tikzpicture}\end{center}}
+\newcommand\callout[3]{%
+  \node[circle, fill=partcol, text=white, font=\heavy\footnotesize, inner sep=0pt, minimum size=15pt,
+    draw=white, line width=1.4pt, blur shadow={shadow blur steps=5, shadow opacity=40}] at (#2,-#3) {#1};}
+\newcommand\num[1]{\tikz[baseline=(n.base)]\node[circle, fill=partcol, text=white, font=\heavy\scriptsize,
+  inner sep=0pt, minimum size=13pt] (n) {#1};}
+
+% "At a glance" fact card for each connection type.
+\newenvironment{glance}[2]{%
+  \begin{tcolorbox}[enhanced, arc=8pt, boxrule=0pt, colback=#1!7, left=12pt, right=12pt, top=9pt, bottom=9pt,
+    before skip=6pt, after skip=12pt, fontupper=\small,
+    overlay={\node[anchor=north east, font=\heavy\tiny, text=#1!80!black, inner sep=8pt] at (frame.north east) {AT A GLANCE};}]
+  {\heavy\Large\color{#1!85!black}#2}\par\vspace{4pt}
+  \renewcommand\arraystretch{1.35}\begin{tabular}{@{}>{\leavevmode\color{muted}}p{0.24\linewidth}>{\leavevmode}p{0.72\linewidth}@{}}}
+  {\end{tabular}\end{tcolorbox}}
+
+% --- Headings --------------------------------------------------------------------------
+\titleformat{\chapter}[display]{\normalfont}{%
+  \pagecanvas{\fill[partcol] (pg.north west) rectangle ([yshift=-9mm]pg.north east);
+    \fill[partcol!12] ([yshift=-9mm]pg.north west) rectangle ([yshift=-11mm]pg.north east);}%
+  {\heavy\small\color{partcol}\MakeUppercase{\partshort}\enspace·\enspace CHAPTER \thechapter}}{2pt}
+  {\heavy\fontsize{30}{34}\selectfont\color{ink}}
+\titlespacing*{\chapter}{0pt}{0pt}{14pt}
+\titleformat{\section}{\heavy\Large\color{ink}}{%
+  \tikz[baseline=(n.base)]\node[fill=partcol, rounded corners=3pt, text=white, font=\heavy\small, inner sep=3pt, minimum width=18pt] (n) {\thesection};}{8pt}{}
+\titlespacing*{\section}{0pt}{18pt}{4pt}
+\titleformat{\subsection}{\heavy\large\color{ink}}{}{0pt}{{\color{partcol}\iArrow}\enspace}
+\titlespacing*{\subsection}{0pt}{12pt}{2pt}
+\renewcommand\thesection{\arabic{chapter}.\arabic{section}}
+\setcounter{secnumdepth}{1}
+\setcounter{tocdepth}{1}
+
+% --- Running heads + thumb tabs ---------------------------------------------------------
+\pagestyle{fancy}
+\fancyhf{}
+\renewcommand{\headrulewidth}{0pt}
+\renewcommand\chaptermark[1]{\markboth{#1}{}}
+\fancyhead[LE]{\footnotesize\color{muted}\heavy Nexus Terminal\enspace\normalfont·\enspace User Guide}
+\fancyhead[RO]{\footnotesize\color{muted}\leftmark}
+\fancyfoot[LE,RO]{\tikz[baseline=(n.base)]\node[fill=partcol, rounded corners=3pt, text=white,
+  font=\heavy\footnotesize, inner sep=3pt, minimum width=20pt] (n) {\thepage};}
+\fancyfoot[RE,LO]{\footnotesize\color{muted}\partshort}
+\fancypagestyle{plain}{\fancyhf{}\fancyfoot[LE,RO]{\tikz[baseline=(n.base)]\node[fill=partcol, rounded corners=3pt,
+  text=white, font=\heavy\footnotesize, inner sep=3pt, minimum width=20pt] (n) {\thepage};}}
+
+% Thumb tabs on the page edge, one slot per part, so you can flick to a part in print.
+\newif\ifthumbs
+\AddToShipoutPictureBG{%
+  \ifthumbs\ifnum\value{guidepart}>0
+  \AtPageLowerLeft{\begin{tikzpicture}[overlay]\pgnode
+    \pgfmathsetmacro\slot{28 + (\value{guidepart}-1)*30}
+    \ifodd\value{page}
+      \fill[partcol, rounded corners=4pt] ([xshift=-7mm, yshift=-\slot mm]pg.north east) rectangle ++(9mm,-26mm);
+      \node[rotate=-90, text=white, font=\heavy\tiny] at ([xshift=-3.6mm, yshift=-\slot mm - 13mm]pg.north east) {\MakeUppercase{\partshort}};
+    \else
+      \fill[partcol, rounded corners=4pt] ([xshift=7mm, yshift=-\slot mm]pg.north west) rectangle ++(-9mm,-26mm);
+      \node[rotate=90, text=white, font=\heavy\tiny] at ([xshift=3.6mm, yshift=-\slot mm - 13mm]pg.north west) {\MakeUppercase{\partshort}};
+    \fi
+  \end{tikzpicture}}\fi\fi}
+
+% \guidepart{colour}{short name}{Title}{tagline}{list of chapters}
+\newcommand\guidepart[5]{%
+  \clearpage
+  \stepcounter{guidepart}\colorlet{partcol}{#1}\renewcommand\partshort{#2}
+  \phantomsection\addcontentsline{toc}{part}{\protect\textcolor{#1}{\arabic{guidepart}}\quad #3}
+  \thispagestyle{empty}\thumbsfalse
+  \pagecanvas{
+    \fill[ink] (pg.south west) rectangle (pg.north east);
+    \fill[#1, opacity=0.9] (pg.north west) rectangle ([yshift=-95mm]pg.north east);
+    \fill[#1!70!black, opacity=0.35] ([yshift=-95mm]pg.north west) -- ++(0,-18mm) -- ([yshift=-95mm]pg.north east) -- cycle;
+    \node[anchor=north west, text=white, font=\heavy\fontsize{150}{150}\selectfont, opacity=0.25]
+      at ([xshift=14mm, yshift=-4mm]pg.north west) {\arabic{guidepart}};
+    \node[anchor=south west, text=white, font=\heavy\small] at ([xshift=24mm, yshift=-72mm]pg.north west) {PART \arabic{guidepart}};
+    \node[anchor=north west, text=white, font=\heavy\fontsize{38}{42}\selectfont, text width=160mm]
+      at ([xshift=24mm, yshift=-73mm]pg.north west) {#3};
+    \node[anchor=north west, text=white!80!#1, font=\large, text width=150mm]
+      at ([xshift=24mm, yshift=-125mm]pg.north west) {#4};
+    \node[anchor=north west, text=white, font=\normalsize, text width=150mm]
+      at ([xshift=24mm, yshift=-145mm]pg.north west) {#5};
+  }\null\clearpage\thumbstrue}
+\newcommand\partitem[2]{{\color{partcol}\large#1}\enspace #2\par\vspace{5pt}}
+
+% Table of contents.
+\RequirePackage{tocloft}
+\renewcommand\cftpartfont{\heavy\large\color{ink}}
+\renewcommand\cftpartpagefont{\heavy\color{ink}}
+\renewcommand\cftchapfont{\color{body}}
+\renewcommand\cftchappagefont{\color{muted}}
+\renewcommand\cftchapleader{\cftdotfill{\cftdotsep}}
+\setlength\cftbeforepartskip{14pt}
+\setlength\cftbeforechapskip{3pt}
+\renewcommand\cfttoctitlefont{\heavy\fontsize{30}{34}\selectfont\color{ink}}
+
+% Symptom → fix cards for troubleshooting.
+\newcommand\fix[2]{%
+  \begin{tcolorbox}[enhanced, breakable, arc=7pt, boxrule=0.5pt, colframe=rule, colback=white, left=11pt, right=11pt,
+    top=8pt, bottom=8pt, before skip=6pt, after skip=8pt, fontupper=\small, parbox=false,
+    title={\heavy\color{ink}\normalsize{\color{partcol}\iBug}\enspace #1}, coltitle=ink, colbacktitle=paper,
+    titlerule=0pt, toptitle=5pt, bottomtitle=5pt, attach title to upper={}, detach title, before upper={\tcbtitle\par\vspace{4pt}}]
+  #2\end{tcolorbox}}
+
+% Big pull-quote line used to break up long stretches.
+\newcommand\breather[1]{\par\vspace{6pt}{\centering\heavy\large\color{partcol}#1\par}\vspace{6pt}}

docs/guide/nexus-guide.tex

@@ -0,0 +1,100 @@
+% Nexus Terminal — User Guide. Build: make (in docs/guide), or: lualatex nexus-guide && lualatex nexus-guide
+\documentclass[10pt,twoside,openany]{book}
+\usepackage{nexus-guide}
+
+\hypersetup{pdftitle={Nexus Terminal: The User Guide}, pdfauthor={Andy Dixon},
+  pdfsubject={SSH, Telnet, RAW, Serial, VNC, RDP, IRC and GitHub in one native app}}
+
+\begin{document}
+\frontmatter
+\pagestyle{empty}
+
+% --- Cover ------------------------------------------------------------------------------
+\pagecanvas{
+  \fill[ink] (pg.south west) rectangle (pg.north east);
+  \shade[left color=accent, right color=violet, opacity=0.55]
+    ([yshift=-60mm]pg.north west) -- ([yshift=-20mm]pg.north east) --
+    ([yshift=-130mm]pg.north east) -- ([yshift=-170mm]pg.north west) -- cycle;
+  \shade[left color=teal, right color=accent, opacity=0.35]
+    ([yshift=-150mm]pg.north west) -- ([yshift=-120mm]pg.north east) --
+    ([yshift=-150mm]pg.north east) -- ([yshift=-185mm]pg.north west) -- cycle;
+  \node[anchor=north east, inner sep=0pt] at ([xshift=-22mm, yshift=-24mm]pg.north east)
+    {\includegraphics[width=34mm]{img/logo.pdf}};
+  \node[anchor=north west, text=white!70!ink, font=\heavy\small] at ([xshift=22mm, yshift=-30mm]pg.north west)
+    {THE USER GUIDE};
+  \node[anchor=north west, text=white, font=\heavy\fontsize{58}{60}\selectfont, text width=170mm]
+    at ([xshift=22mm, yshift=-36mm]pg.north west) {Nexus\\[-2pt]Terminal};
+  \node[anchor=north west, text=white, font=\Large, text width=150mm]
+    at ([xshift=22mm, yshift=-88mm]pg.north west)
+    {Every terminal you need. One window.\\Zero faff.};
+  \node[anchor=north west, text=white!65!ink, font=\normalsize, text width=150mm]
+    at ([xshift=22mm, yshift=-110mm]pg.north west)
+    {SSH\enspace·\enspace Telnet\enspace·\enspace RAW TCP\enspace·\enspace Serial\enspace·\enspace VNC\enspace·\enspace RDP\enspace·\enspace IRC\enspace·\enspace GitHub\enspace·\enspace Local shells};
+  \node[anchor=south west, inner sep=0pt] at ([xshift=22mm, yshift=22mm]pg.south west)
+    {\begin{tikzpicture}
+      \node[inner sep=0pt, draw=white!25!ink, line width=0.6pt, rounded corners=4pt] {\includegraphics[width=166mm]{img/ssh.png}};
+    \end{tikzpicture}};
+  \node[anchor=south east, text=white!55!ink, font=\footnotesize, align=right]
+    at ([xshift=-22mm, yshift=24mm]pg.south east) {Version 3.0.1\\October 2026\\dixon.cx};
+}\null
+\cleardoublepage
+
+% --- How to use this guide ----------------------------------------------------------------
+\colorlet{partcol}{accent}
+{\heavy\fontsize{30}{34}\selectfont\color{ink} Start here.\par}
+\vspace{2pt}{\large\color{muted} (Yes, even if you never read manuals. \emph{Especially} then.)\par}
+\vspace{10pt}
+
+This guide is built for skimming. You do \textbf{not} have to read it in order, cover to cover, like it's
+homework. Find the bit you need, grab it, get back to work. Every chapter opens with the time it takes and
+what you'll be able to do afterwards, and a \textbf{TL;DR} if you only want the gist.
+
+\vspace{4pt}
+{\heavy\large\color{ink}\iMap\enspace I just want to…}\par\vspace{2pt}
+\renewcommand\arraystretch{1.5}
+\begin{tabularx}{\linewidth}{@{}X>{\raggedleft\arraybackslash}p{52mm}@{}}
+  \toprule
+  …get connected to something \emph{right now} & \hyperref[ch:start]{Five-minute start}, p.\,\pageref{ch:start}\\
+  …work out what all the buttons do & \hyperref[ch:tour]{The grand tour}, p.\,\pageref{ch:tour}\\
+  …SSH into a server (keys, jump hosts, 2FA) & \hyperref[ch:ssh]{SSH}, p.\,\pageref{ch:ssh}\\
+  …talk to a router or Arduino over a USB cable & \hyperref[ch:serial]{Serial}, p.\,\pageref{ch:serial}\\
+  …copy files to and from a server & \hyperref[ch:files]{Files}, p.\,\pageref{ch:files}\\
+  …type the same thing into ten servers at once & \hyperref[ch:repeat]{Never type it twice}, p.\,\pageref{ch:repeat}\\
+  …keep my passwords safe & \hyperref[ch:secrets]{Passwords \& the vault}, p.\,\pageref{ch:secrets}\\
+  …keep two computers in step & \hyperref[ch:move]{Moving house}, p.\,\pageref{ch:move}\\
+  …fix something that's broken & \hyperref[part:fix]{When things go wrong}, p.\,\pageref{ch:trouble}\\
+  …just see the keyboard shortcuts & \hyperref[app:keys]{The cheat sheet}, p.\,\pageref{app:keys}\\
+  \bottomrule
+\end{tabularx}
+
+\vspace{8pt}
+{\heavy\large\color{ink}\iSparkle\enspace The little boxes}\par\vspace{-2pt}
+\begin{multicols}{2}\small
+\begin{tldr}The whole chapter in three lines.\end{tldr}
+\begin{quickwin}Something you can try in under a minute.\end{quickwin}
+\begin{protip}A trick that saves you time later.\end{protip}
+\columnbreak
+\begin{headsup}A thing that might trip you up.\end{headsup}
+\begin{danger}Could lose data or weaken security. Read it.\end{danger}
+\begin{sidequest}Interesting, but not needed to get the job done.\end{sidequest}
+\end{multicols}
+
+\vspace{-6pt}
+{\small\color{muted}\textbf{Shortcuts:} \mod{} means \kbd{Ctrl} on Windows and Linux, \kbd{\ph{E1C4}} (Command) on a Mac. So
+\keys{\mod+K} is \kbd{Ctrl}+\kbd{K} or \kbd{\ph{E1C4}}+\kbd{K} depending on your machine.}
+
+\clearpage
+\pagestyle{plain}
+{\hypersetup{linkcolor=body}\tableofcontents}
+\clearpage
+
+\mainmatter
+\pagestyle{fancy}
+\input{chapters/part1-start}
+\input{chapters/part2-connect}
+\input{chapters/part3-faster}
+\input{chapters/part4-safe}
+\input{chapters/part5-yours}
+\input{chapters/part6-fix}
+\input{chapters/appendix}
+\end{document}

docs/guide/tools/demo-shell.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+# ForceCommand for the throwaway screenshot sshd: never a login shell (no ~/.profile, no byobu).
+DEMO_HOME=$1 SFTP_SERVER=$2
+export LC_ALL=C.UTF-8
+case "$SSH_ORIGINAL_COMMAND" in
+  *sftp*) exec "$SFTP_SERVER" -d "$DEMO_HOME" ;;
+  ?*) cd "$DEMO_HOME" && HOME="$DEMO_HOME" exec bash --norc --noprofile -c "$SSH_ORIGINAL_COMMAND" ;;
+esac
+cd "$DEMO_HOME" || exit 1
+export HOME="$DEMO_HOME" PS1='\[\e[1;32m\]andy@atlas\[\e[0m\]:\[\e[1;34m\]\w\[\e[0m\]\$ '
+row() { # boxed line, padded on visible width
+  local plain; plain=$(printf '%b' "$1" | sed 's/\x1b\[[0-9;]*m//g')
+  printf '\e[1;36m│\e[0m  %b%*s\e[1;36m│\e[0m\n' "$1" $((44 - ${#plain})) ''
+}
+printf '\e[1;36m╭──────────────────────────────────────────────╮\e[0m\n'
+row 'Welcome to \e[1matlas\e[0m · Debian 13 · kernel 6.12'
+row 'Load \e[32m0.42\e[0m   Memory \e[33m61%\e[0m   Disk \e[32m38%\e[0m'
+row 'Last deploy: \e[1m2 hours ago\e[0m by andy'
+printf '\e[1;36m╰──────────────────────────────────────────────╯\e[0m\n\n'
+printf '\e[1;32m$\e[0m ls -l --color\n'; ls -l --color=always
+printf '\n\e[1;32m$\e[0m ./deploy.sh --dry-run\n'
+for s in "Resolving build" "Uploading artefacts" "Rolling out to 4 nodes" "Health checks"; do
+  printf '  \e[32m✔\e[0m %-26s \e[2m%s\e[0m\n' "$s" "$((RANDOM % 900 + 100))ms"
+done
+printf '  \e[33m⚠\e[0m 1 warning: \e[1mnginx.conf\e[0m has a deprecated directive\n'
+printf '  \e[1;32mDone.\e[0m Nothing was actually deployed (dry run).\n\n'
+exec bash --norc --noprofile -i