Two root-cause fixes surfaced by cluster smoke v74v4 (sweep_smoke-a2dfc6d99):
Bug D — DBN parser price scaling:
- BidAskPair::price_to_f64/price_from_f64 used /1e12 / *1e12 from test-data
calibration. DBN production uses 1e-9 nanoprice (the DBN standard). ES at
5500 raw 5_500_000_000_000 → 5.5 instead of 5500. Smoke trade records
showed entry_px=5.24 instead of expected ~5240 ES index points (1000×
too small). Fix: 1e12 → 1e9 in both functions. Round-trip symmetric;
tests updated.
Bug C-b — corrupt top-of-book sentinel:
- Per-level sanitization (Task 15) zeros each unhealthy MBP-10 level
individually. At session-boundary events with all 10 levels invalid,
the book becomes uniformly zero. apply_fill_to_pos then reads
bid_px[0]=0 / ask_px[0]=0 → vwap_entry=0 → trade record entry_px=0
(zero sentinel in v74v4 CSV, 162/1024 trades in n59t4).
- Fix: pre-validate top-of-book in apply_snapshot_kernel. If
bid_px[0]/ask_px[0]/bid_sz[0]/ask_sz[0] are non-finite or
bid_px[0]<=0/ask_px[0]<=0/bid_sz[0]<=0/ask_sz[0]<=0, atomically skip
the entire snapshot (book/prev_mid/atr_mid_ema unchanged). Add
per-backtest snapshots_skipped_d counter for observability.
Test corrupt_top_of_book_skips_snapshot_and_increments_counter validates
NaN top-price + zero top-size cases both increment the counter without
mutating state, and that a subsequent valid snapshot updates normally.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>