avewright/opening-model

99M opening specialist (squares64)

Same 99M squares64 architecture as avewright/chess-transformer-100m-squares64, finetuned on ≥26-piece positions (one-hot best first move) from Lichess/chess-position-evaluations via avewright/lichess-opening-bestline.

This file is latest.pt at opening-FT step 8000 (2026-09-14 14:42 UTC). Train loss ~1.7585. Frozen holdout hard CE ~1.4045.

Not the generalist incumbent, the puzzle expert, the Syzygy expert, or the endgame expert.

Training

• Warm start: public 99M latest.pt (weights only), then full resume.
• Split: position-hash 80/20 (seed 277). Frozen piece-stratified val 8192.
• One-hot PV1 (soft_alpha=0). Pieces 26–32.
• Polar-NorMuon, bs=528. Best disk ckpt at upload: step 8000.

Files

• latest.pt
• step_008000.pt
• model_config.json
• train.log
• pack.json