Findings:
- Production Mamba2 (gpu_dqn_trainer) is coupled to SH2=256 trunk +
ofi_embed + ISV[8] temporal routing — not portable to Phase E.
- ml-alpha::mamba2_block::Mamba2Block is from-scratch, fully
configurable (in_dim/hidden_dim/state_dim/seq_len), GPU-pure with
forward_train/backward/AdamW. Used in Phase 1d.2 to lift AUC 0.50
to 0.66. ml-alpha is already a workspace dep of ml.
- GRN skipped for E.4.A — Mamba2 output goes straight to C51 head.
Reintroduce GRN in E.4.B if Sharpe gates don't pass.
- Controller-at-inference: kernel has no training-mode branches;
Wiener state preserved across episodes/cost cells for natural
live-deployment simulation.
Revises Tasks 8-10 of the plan: use Mamba2Block API instead of
writing custom kernels. Only new CUDA needed: alpha_c51_grad_input
(C51 gradient w.r.t. input features, for Mamba2 backward chain).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
588a6d38af