Nebium-Large (762M) — Autoregressive Chess Transformer

Decoder-only causal transformer trained on competitive Lichess UCI coordinate move sequences.

• Parameters: 762 Million ($L=36$, $d_{\text{model}}=1280$, $H=20$)
• Architecture: RoPE positional encoding, SwiGLU non-linearity, Pre-RMSNorm
• Vocabulary: 5,000-merge BPE