v0.4.2-rc.1

Features

• (search) Record every reverse futility candidate, fired or not [bench 8182450]
• (search) Add principal variation search [bench 7184673]
• (search) Skip hopeless captures in quiescence [bench 6708286] [elo +50 ±24 (sprt [0, 10] passed, 530 games, 10+0.1, vs 24ef995)]
• (search) Add static exchange evaluation [bench 6708286]
• (search) Order captures by static exchange evaluation [bench 6146070] [elo +12 ±18 (sprt [-10, 0] inconclusive, 840 games, 10+0.1, vs master)]
• (search) Skip losing captures in quiescence [bench 5684750] [elo +24 ±19 (sprt [-10, 0] passed, 746 games, 10+0.1, vs 6e6fdec)]
• (search) Reduce late quiet moves by one ply [bench 4395471] [elo +44 ±22 (sprt [0, 10] passed, 648 games, 10+0.1, vs 899197c)]

Performance

• (search) Score the quiet moves only when the search reaches them [bench 6146018] [speed +3.4%]
• (board) Mask the castling rights, step the repetition walk in twos [bench 4395471] [speed +3.5%]
• (search) Sort the keys and put the moves in order once [bench 4395471] [speed +2.1%]

Refactor

• (search) Leave the swap's gain array uninitialised [bench 5684750]

Development

• (bench) Let the residuals command set the reservoir cap
• (bench) Score the terminal positions the replay reaches
• (docs) Correct three verdicts in the experiments ledger
• (docs) Record that on-demand move picking measured slower
• (bench) Count the rows whose claim overstates the reference
• (docs) Record the tuning that measured slower
• (ci) Count how the games in a match ended
• (ci) Keep the games and a manifest from every strength run

Docker image: ghcr.io/aywrite/arche-lichess-bot:v0.4.2-rc.1 (sha256:d383e13786d14a8e1b3bdf4b76d336077b304919bd50aa6393cb61559930c65a)

Performance compared to v0.4.1 | +78 ±77 Elo (50 games)

Estimated rating | 2268 ±34 on the ccrl blitz scale (104 games)