jgrusewski f86353840e fix(dqn): unstick IQN trunk gradient — drop iqn_readiness multiplier from SAXPY scale
`apply_iqn_trunk_gradient` and the parallel VSN-range SAXPY both scaled their
contribution by `iqn_lambda × iqn_readiness × iqn_budget`. The readiness
scalar initialises to 0.0 and only ramps up when `iqn_loss_ema` drops below
`iqn_loss_initial` — but that improvement requires the trunk to learn IQN's
gradient, which the readiness gate just blocked. Bootstrap deadlock:
trunk_iqn=0.0000 across every observed L40S epoch, downstream strangling
direction-Q discrimination → eval strict-argmax glues to one direction →
22-34 trades per 858k-bar window vs healthy 1257-trade burst at the one
epoch where the gate momentarily lifted.

iqn_budget already throttles the IQN contribution via the per-component
budget controller (60% IQN, ISV-driven), so readiness was an additive
band-aid that became load-bearing. New scale: `iqn_lambda × iqn_budget`.

The `iqn_readiness` field stays on `self` because the C51 loss kernel
launch site reuses `iqn_readiness_dev_ptr` as a CVaR-alpha pointer
(gpu_dqn_trainer.rs:~16227) — that semantic overload is broken in a
different way (CVaR α=0 is degenerate) and is tracked for follow-up.

Verified on cluster trace `train-multi-seed-vg2r9` (epochs 0–13):
trunk_iqn=0.0000 every epoch, q_gap_comp=0.00 every epoch, val
trade_count locked at 22–34 except epoch 2 (1257 trades) where the
gate accidentally cleared.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-26 18:04:36 +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%