jgrusewski 5d5a2c1f3d fix(direction+magnitude): complete C51 variance bias elimination
Root cause: C51 distributional softmax structurally favors zero/low-variance
actions (Flat for direction, Small for magnitude). This created irrecoverable
feedback loops through FOUR paths: gradient, Bellman target argmax, action
selection, and the Q-gap conviction filter.

Direction branch (new):
- Zero C51 gradient for direction (d==0) — same treatment as magnitude
- Boltzmann softmax replaces argmax for direction selection (tau=2×Q_range)
- 2× MSE gradient amplification for direction branch head
- Mean advantage (not C51 softmax) for Bellman target argmax at d==0
- Q-gap conviction filter REMOVED from training path (redundant with
  Boltzmann, harmful after high-Sharpe epochs where Bellman max bootstrap
  raises Q(Flat) towards Q(directional), shrinking the gap)

Magnitude branch (Bellman target fix):
- Mean advantage for Bellman target argmax at d==1 in both MSE + C51 kernels
- Proper softmax retained for online_eq and target_eq (learning objective)

Metric fixes:
- Diversity denominator: 9 → 7 (Flat forces mag=Half, max reachable is 7)
- Threshold: 0.5% of total → 1% of directional (Flat-dominant policies
  mechanically killed diversity under the old metric)

Result: 7/7 dir×mag diversity sustained epochs 7-10, Flat stable at 7-9%
(was 60-87% growing). 19/19 smoke tests pass.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-04-09 01:02:20 +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%