Testing

Published on
January 21, 2026
Wasted Testing Comes from Picking the Wrong Layer: Use the Smallest Layer That Proves the Behavior, Mock the Seam Not the System
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The biggest waste in testing is writing a pile of tests that pass easily but never cover real failures. Through "pick the smallest layer that proves the behavior" and "mock the seam, not the system," a breakdown of test layering and its tradeoffs.

Wasted Testing Comes from Picking the Wrong Layer: Use the Smallest Layer That Proves the Behavior, Mock the Seam Not the System