I made a free and open source chess database. It's useful for personal game study and gathering statistics across sites. Supports import from lichess, chess.com, FICS and PGN then runs Stockfish and Maia over every game.

With it you can analyze your games, take notes on positions and look up openings. The self hosted web version includes a remote-runner that allows connecting engines running on other machines (finally, the CPUs of the AI server at work come to use :D) and an MCP server with a live board to push positions and comments to.

Roadmap: iOS and Android companion apps, a sync service, multi-engine analysis, and a correspondence game mode supporting multiple long running calculations.

Looking forward to feedback and critique.

Docker, Windows, Mac: https://blunderbase.org Demo: https://demo.blunderbase.org (read-only)