CodeNote

CodeNote is a lightweight desktop markdown/text editor with a live preview and a native terminal, built on Tauri. It's a single window, single surface — editor, preview, and an optional terminal drawer, no dashboards or settings screens. The idea is narrow but deep: few features, but the ones it has (syntax highlighting, diagrams) are full-featured rather than a cut-down subset.

What's in it

• Editor — CodeMirror 6, with language packages for JS/TS/JSX/TSX, Python, CSS, HTML, JSON, YAML, and Markdown, auto-detected from the file extension. It uses a dedicated near-black editing surface and mirrors the Atom Dark Prism palette used by fenced code in the preview.
• Live markdown preview — a remark → rehype pipeline (GFM tables, task lists, footnotes, headings, blockquotes, relative image resolution, external links opened in the OS browser instead of in-app).
• Code highlighting — the full vendored PrismJS 1.30.0 bundle: every language Prism ships, not a hand-picked list, plus a curated plugin set (copy-to-clipboard, line numbers, brace matching, inline color swatches, treeview, and more).
• Diagrams — fenced ```mermaid blocks render via Mermaid, configured permissively (loose security so click handlers/tooltips work, HTML labels, high size/edge limits) rather than locked to a small diagram subset. Theme is hand-matched to the app's blue-slate palette.
• Terminal — an xterm.js-backed native PTY session, toggled independently of whatever file is open.
• Tabs — multi-tab editing with dirty-state tracking, close/cycle/new.

Stack

Tauri 2 (Rust shell) + React 19 + Vite 7, with CodeMirror 6 for editing, unified/remark/rehype for markdown, vendored PrismJS for highlighting, Mermaid 11 for diagrams, and xterm.js for the terminal.

Keyboard shortcuts

Shortcut	Action
Ctrl/Cmd+S	Save
Ctrl/Cmd+`	Toggle terminal
Ctrl/Cmd+N	New tab
Ctrl/Cmd+O	Open file
Ctrl/Cmd+W	Close tab (confirms if dirty)
Ctrl/Cmd+Tab / Shift+Tab	Cycle tabs

File I/O

Tauri's dialog and fs plugins handle open/save — saves in place if the file has a known path, otherwise prompts a save-as dialog. No cloud sync, no auto-save beyond explicit save.

Explicitly out of scope

Multi-window, a plugin/extension system, cloud sync, collaborative editing, a settings UI, and a command palette. None of these are planned — the app is meant to stay small.

Development

npm install
npm run dev      # Vite dev server
npm run tauri dev  # Tauri desktop shell
npm run build     # tsc + production build

See SPEC.md for the full rendering contract and design notes.