Error and Correctness Traps

Overview

Common bugs grouped by domain: floats that won't compare equal, retries that hammer a downed service, singletons that wreck testability, and others. When you write code in one of these domains, stop and run the matching checks before you commit.

This is a rigid skill. Jump to the sub-section that matches what you're writing and run that sub-section's checks.

These checks matter most when code will reach real users in production. In MVPs, prototypes, internal dev tools, and one-off scripts where the architecture is still in flux, prefer the simplest thing that works.

When to invoke

Invoke when you're about to: