Feature Engineering Cookbook
Use this checklist when adding or changing ML features.
Design Rules
- Prefer causality-safe features only.
- Keep naming conventions consistent (
TF*_ALT_*,TF*_BTC_*). - Avoid leaking future information through timestamp alignment.
Train/Infer Parity
- Ensure feature trimming and windows match inference path.
- Keep schema changes backward-compatible only when needed.
- Add tests for transformed output shape.
Practical Workflow
- Add feature in transform path.
- Regenerate dataset export.
- Train model and inspect holdout/walk-forward quality.
- Verify inference still loads and predicts with new feature set.
- Document feature intent and impact.
Anti-Patterns
- Adding highly unstable features without drift monitoring.
- Mixing experiment-only features into production path silently.