jgrusewski 25f5ce99b6 feat(rl): Phase 4.3 — V_dq → PPO advantage swap + target net soft-update
Activates DuelingQHead's V output as the PPO advantage baseline,
replacing scalar value_head's contribution. Also wires soft-update
of DuelingQHead's target net (was deferred from 4.2).

Two changes:

1. DuelingQHead.soft_update_target(): reuses dqn_target_soft_update
   kernel (generic element-wise blend with τ from ISV[401]) across
   all 4 weight tensors (w_v, b_v, w_a, b_a). Called once per training
   step after Adam, mirroring DQN's pattern.

2. compute_advantage_return call: v_pred_d → dueling_v_d,
   v_pred_tp1_d → dueling_v_tp1_d. PPO advantage is now:
       A(s_t, a_t) = E_Q_C51(s_t, a_taken) − V_dq(s_t)
       returns(s_t) = r_t + γ(1−done) × V_dq(s_{t+1})
   value_head still trains via MSE on returns for diagnostic
   comparison; can be retired in a future commit if V_dq proves
   itself.

Phase 4.2 validated structurally at b=1024 5k that DuelingQHead's
training does not perturb Plan A v2's dynamics (qpa tracked within
0.02 at every milestone). Phase 4.3 is the smallest possible commit
that USES V_dq downstream — fully de-risked by 4.2's structural test.

Cluster expectation: qpa trajectory roughly matches Plan A v2 (V_dq
calibrated by joint training on same Bellman reward signal as C51,
so cross-architecture scale issue from Phase 3.2 doesn't apply here).

Validated:
  - cargo build --release clean
  - integrated_trainer_smoke 1 step passes
  - alpha_rl_train --steps 3 --b 128 under compute-sanitizer: 0 errors,
    l_q=0.024, l_v=0.0003 (slightly higher than Plan A v2's 0.0001
    because V_scalar now sees different gradient prop now that V_dq
    drives advantage — still healthy)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-30 09:14:46 +02:00

Foxhunt

Production HFT trading system in Rust.

Architecture

The workspace contains 32 crates organized as follows:

Core Libraries (16)

Crate Purpose
trading_engine Order processing, FIX 4.4, IB TWS, SIMD, RDTSC timing
risk VaR, Kelly, circuit breakers, kill switches, compliance
risk-data Risk data types and shared structures
trading-data Trading data types
ml DQN Rainbow, PPO, TFT, Mamba2, ensemble inference
ml-data ML data types and feature definitions
data Market data ingestion and storage
backtesting Replay engine, strategy tester
adaptive-strategy Ensemble execution, microstructure analysis
common Shared types, resilience, error handling
storage S3 and local model storage
model_loader Model serialization and loading
market-data Market data feed handlers
database PostgreSQL access layer (SQLx)
config Configuration management
tli CLI commands and tooling

Services (8)

Service Purpose
backtesting_service gRPC backtesting service
broker_gateway_service FIX routing, broker connectivity
trading_service Core trading operations
ml_training_service Model training orchestration
data_acquisition_service Market data acquisition
trading_agent_service Autonomous trading agents
api_gateway gRPC API gateway with auth
web-gateway Axum REST + WebSocket gateway

Frontend

web-dashboard/ -- React 19 + TypeScript + Vite + TradingView charts.

Building

# Check compilation (no PostgreSQL required)
SQLX_OFFLINE=true cargo check --workspace

# Run tests for a specific crate
SQLX_OFFLINE=true cargo test -p <crate> --lib

# Clippy
SQLX_OFFLINE=true cargo clippy --workspace

ML Models

Four production model architectures on Candle v0.9.1 with CUDA:

  • DQN Rainbow -- Deep Q-Network with prioritized replay, dueling heads, noisy nets
  • PPO -- Proximal Policy Optimization with GAE and LSTM policies
  • TFT -- Temporal Fusion Transformer for multi-horizon forecasting
  • Mamba2 -- State space model for sequence prediction

Each model has a standalone trainer and a UnifiedTrainable adapter for the hyperopt pipeline.

Infrastructure

  • Git: Gitea at git.fxhnt.ai (Tailscale-only), Scaleway DEV1-S
  • Observability: OpenTelemetry OTLP (env OTEL_EXPORTER_OTLP_ENDPOINT)
  • Database: PostgreSQL with SQLx offline mode for CI

License

Proprietary. All rights reserved.

Description
No description provided
Readme 849 MiB
Languages
Rust 88.2%
Cuda 7.7%
Python 1.3%
Shell 1.1%
PLpgSQL 0.8%
Other 0.8%