$ show marktext/marktext
MarkText is a cross-platform desktop markdown editor (Electron + Vue 3) powered by the Muya WYSIWYG engine. It provides real-time rendering of CommonMark, GFM, and extended syntax including KaTeX math, mermaid/plantuml diagrams, footnotes, tables, task lists, and 30+ themes. The monorepo contains four packages: `desktop` (Electron shell with IPC, preferences, spellcheck, export), `muya` (TypeScript core editor with block-based state, snabbdom rendering, undo/redo via ot-json1, clipboard, and floating UI components), `muyajs` (legacy JavaScript engine, still present for partial feature parity), and `website` (Next.js documentation site). The architecture follows a block tree pattern where each block type (paragraph, heading, list, table, etc.) is a subclass with consistent parent/content interfaces. Communication between the Electron main and renderer processes uses typed IPC channels. The codebase demonstrates strong software engineering practices with extensive unit and e2e test coverage (Playwright, Vitest), reproducible builds (pnpm monorepo), and a focus on regression testing for edge cases. However, the ongoing migration from the legacy `muyajs` engine to the new `muya` engine introduces some code duplication and technical drift, and some modules retain prototype-style JavaScript alongside modern TypeScript classes.
The LLM identified 5 files worth highlighting for reuse:
A generic doubly linked list implementation used for managing block children in the editor's block tree. Provides O(1) insertion/deletion, iteration helpers, and integrates with ILinkedNode interface. Could be extracted into any project that needs efficient ordered child management, such as a text editor or hierarchical data structure. Demonstrates non-obvious skill in balancing performance with ergonomics.
Typed publish/subscribe event system with built-in DOM event attachment/detachment. Supports once-listener, returns subscription IDs for cleanup, and handles iteration safety (prevents mutation during emit). Self-contained and dependency-free, reusable in any JavaScript/TypeScript application for decoupled communication. Demonstrates careful handling of edge cases like listener leaks and concurrent modification.
Abstract base class for floating UI components (format toolbar, image picker, etc.). Encapsulates show/hide lifecycle, positioning via Floating UI's autoUpdate and computePosition, resize observer, and scroll handling. The subclass pattern allows easy creation of consistent popover menus with keyboard navigation. Demonstrably reusable: six different UI components (link tools, emoji selector, code block language selector, etc.) inherit from this class.
Utility for rendering and dynamically syncing code block line numbers. Uses delta-based span updates and Range API for precise positioning in wrap mode, avoiding full DOM rebuild on every edit. Self-contained functions that take a container element and return update methods. Could be extracted into any code editor component (web or Electron) needing efficient line number rendering. Demonstrates advanced DOM manipulation and performance awareness.
Content-addressed identifier allocator for tracking document save/dirty state. Uses a counter-based ID that resets on content changes, avoiding depth-based collision issues of naive approaches. Integrates with editor events to mark clean/dirty without relying on full history length. Reusable in any application that needs 'save state' detection independent of undo stack depth.