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Prototype
Synopsis editor
A zero-dependency markdown editor with live syntax highlighting. Dark theme, keyboard shortcuts, no distractions.
Why we built this
Every markdown editor is bloated. We wanted something fast, distraction-free, with live syntax highlighting, that could be opened in a single HTML file without installing anything.
How we built it
One HTML file with contenteditable div. Node.js backend. Every keystroke triggers line-by-line classification: headings, quotes, checkboxes, tables, lists, bold, code, links, stat numbers. Cursor position preserved via character offset mapping. Cmd+S saves, Tab inserts spaces, paste strips formatting. No frameworks, no build step, zero dependencies.
What's next
Personal writing tool. Fast, reliable, does exactly what we need. Not planning to turn it into a product. Sometimes the best tool is the one you build for yourself and never release.
Built with
Node.js
Vanilla JS
contenteditable API
Character Offset Mapping
Zero Dependencies
