HedgeDoc

Real-time collaborative markdown note editor you can self-host — write together with rich formatting and seamless sharing.

Open source alternative to:

Google Docs

Notion

HedgeDoc (formerly CodiMD) is an open-source, self-hosted realtime collaborative markdown editor. Multiple users can edit the same document simultaneously with real-time sync, making it ideal for meeting notes, documentation, and knowledge sharing.

HedgeDoc supports the full CommonMark markdown spec plus many extensions: math equations (MathJax/KaTeX), diagrams (Mermaid, PlantUML, Graphviz), syntax-highlighted code blocks, interactive checklists, and embedded media. Documents can be published as presentations (using reveal.js), exported to PDF, or shared via public link.

For teams that collaborate on text documents, HedgeDoc provides a lightweight, privacy-friendly alternative to Google Docs or Notion. It integrates with various authentication providers (LDAP, OAuth, email) and can be deployed with Docker. Each document gets a shareable URL and notes are stored with full version history.