Import your games from Lichess and Chess.com. Stockfish 18 finds the positions where you failed. Drill them as puzzles until the right move is reflex.
View source on GitHub ↗
You reviewed the game. The engine flagged the blunder. You nodded, closed the tab, played another game. A week later — same pattern, same mistake, same frustration.
Lichess analysis doesn't let you drill positions. Chess.com review is paywalled. Neither builds a persistent library of your mistakes. The feedback loop has a gap.
This tool fills it.
Lichess or Chess.com username. Both at once. Full history, all time controls. Public API — no credentials.
Your games are analyzed with Stockfish, openings detected, blunders marked and explained.
Each blunder becomes a puzzle. Filter by opening, game phase, difficulty. Eval bar, best-move arrows, hints. Track accuracy over time.
Docker. Nothing leaves your machine. No accounts, no tracking.
# run it
$ docker run -p 8000:8000 \
-v $(pwd)/data:/app/data \
ghcr.io/mrlokans/blunder-tutor:latest
# localhost:8000 → username → drill