Introduction

Most production bugs are not exotic. They are the same handful of mistakes, repeated under deadline pressure. Here are five of them and where tooling genuinely helps.

1. Silent Type Coercion

Loose equality and implicit conversion still cause a surprising share of incidents. Static analysis catches these instantly, and an assistant can annotate an untyped codebase far faster than you can by hand.

2. Unhandled Async Failures

A promise without a rejection path is a future incident. Ask your tooling to audit every async boundary for error handling — it is mechanical work with a high payoff.

3. Copy-Paste Divergence

Duplicated logic drifts. When one copy gets a fix and the other does not, you get bugs that only reproduce on some routes.

Detection is the hard part, and it is exactly what pattern matching is good at.

4. Leaky Abstractions

When a helper needs six flags, it is not a helper any more. Use review tooling to flag functions whose parameter count keeps growing.

5. Missing Edge-Case Coverage

Empty arrays, zero, null, and the very large input. Generate these cases automatically and you will find the gaps before your users do.