AFFiNE
Open-source privacy-first collaborative workspace combining notes, docs, whiteboards, and knowledge management in one self-hosted Notion alternative.
Penpot
Open-source design and prototyping platform for cross-domain teams with real-time collaboration, SVG-based design, and developer-friendly features - free alternative to Figma.
draw.io (diagrams.net)
Self-host the full diagrams.net diagramming suite with realtime collaboration, Confluence-style sharing, and on-premise storage for architecture docs.
Excalidraw
Open-source virtual whiteboard for brainstorming, diagramming, and architecture sessions with real-time collaboration and offline-friendly files you can self-host anywhere.