# Gotchas

Append-only lessons about feature engineering for recsys in a two-sided trust
marketplace. Each entry is a specific failure point and the resolution, with a
date. Read before recommending an intervention — the problem you are about to
solve may already be documented here.

---

No known gotchas yet. Add them here as they are discovered.

## Template

```markdown
### {Short, specific title}
{1-3 sentences describing what went wrong, what the symptom looked like, and
what the root cause turned out to be.}
**Fix:** {The specific action that resolved it.}
**Rules that prevent this:** [`rule-name`](references/rule-name.md)
Added: YYYY-MM-DD
```
