A database you own
PGN files in folders you can read and back up. The index is only an index.
Caissa
A desktop chess workbench — a lighter ChessBase.
Your games stay on your own disk as ordinary PGN. A bundled Stockfish analyses them, the explorer walks your openings and shows how they actually went, and your repertoire drills itself. No account, no cloud library, no telemetry.
Download
Also for Windows, macOS and Linux · run from source
Openings, judged
Walk a collection's tree and see the score, the trend, and where the points went.
Repertoires that drill
A lichess study becomes spaced-repetition lines you play blindfold.
Works offline
The engine, your games, the opening book and every exercise need no connection.