Matra, the editor that edits its own homepage

Field notes

The framework uses extension arrays to shape one core into materially different interfaces, including a deliberately restricted comment box and a one-block chat composer. Its homepage exposes editing behavior directly: slash commands, Markdown shortcuts, grouped undo, smart punctuation, and DOM-free Markdown conversion are demonstrated in the page itself. The extract reports 857 tests and benchmarks against Tiptap and Lexical on documents up to 2,000 paragraphs, while noting that Slate was not measured.