Hard Lines
Breadth-first spaced repetition for chess openings
What it does
Depth-first opening trainers bury you in one long line. Hard Lines imports any PGN (Lichess studies, your own files, course exports) and drills your early choices across the whole tree first, then goes deeper as you're ready, using spaced repetition to keep it all fresh. Bring your own repertoire, no marketplace lock-in.
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- PAPlay against well-known chess players' openings2022 · d2frm2q2a7fq8v.cloudfront.net · ▲5
Hi, this is my first HN submission so please forgive the rough edges. For this project gathered chess positions from some well-known chess players with a lot of games. (Usually ~25k games and 1M+ positions. The most for any player was GM Aman Hambleton with 1.8M positions indexed.) With each board position I create a probability distribution of moves the player has made from that position. Then, I simply draw from that distribution (with sampling temperature) to choose a move. As long as there's at least one game with a given position, you can keep playing. You'll see that it's pretty easy…
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Life & fun · 10d ago · louisabraham.github.io
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Life & fun · Aug 2026 · toneyalexander.github.io
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