HedgeDoc Collaborative Markdown

HedgeDoc is an open-source collaborative, real-time, multiplatform Markdown editor that enables teams to create and share documents, presentations, and notes in real-time, inspired by HackMD and formerly known as CodiMD. Maintained by the HedgeDoc community since 2019 as a community-driven fork of HackMD, the project has over 5,400 stars as of 2026 and is used by universities, open-source communities, and enterprises for collaborative documentation. Key features include: real-time collaboration (multiple users editing the same document simultaneously with live cursor tracking and conflict-free editing), Markdown rendering (GitHub-flavored Markdown with tables, task lists, strikethrough, emoji, and automatic table of contents), slide mode (creating reveal.js presentations directly from Markdown with configurable themes and speaker notes), math support (LaTeX math rendering via MathJax for inline and block equations), diagram support (drawing sequence diagrams, flowcharts, and Gantt charts via Mermaid, PlantUML, and Graphviz inline syntax), code highlighting (syntax highlighting for over 100 programming languages via highlight.js), image upload (drag-and-drop upload to Imgur, MinIO, Azure, S3, or embedded base64), version history (document revision history with diff comparison and restoration), permissions (three levels: freely accessible, editable by signed-in users, and locked to owner, plus password protection), guest access (allowing anonymous editing without registration), authentication (local, LDAP, GitHub, GitLab, Google, SAML, and OpenID Connect), import and export (clipboard, URL, GitHub Gist import, and Markdown, HTML, PDF export), and self-hosted Docker deployment with PostgreSQL or SQLite backend.