Operationalize Every Fix

When a bug is found and fixed, don't stop at the fix. Extract the full learning:

The Protocol

1. Test-First (Before Fixing)

Write a reproduction test FIRST:

Bug reported → Write failing test → Confirm test fails → Fix bug → Confirm test passes

The test proves the bug exists. The fix proves the test works. Don't reverse this.

2. Expand Test Coverage

After fixing, ask:

• What's the class of this bug? (off-by-one, null handling, async race, etc.)
• Write tests for the whole class, not just this instance
• Edge cases: empty input, max values, concurrent access, unicode, timezone