- Published on
Tests can pass while production still breaks when the suite proves the intended path but misses retries, concurrency, dirty data, and rollout state.
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- Published on
Why some bugs appear only under production load: how concurrency, data shape, queues, retries, and partial failures change behavior in real systems.- Published on
Why a database index can exist and still fail to speed up a query: selectivity, row estimates, composite index order, and ORDER BY LIMIT behavior.- Published on
Why production caches return stale or contradictory data: cache-aside races, invalidation gaps, TTL drift, local cache divergence, and safer rollouts.- Published on
A practical debugging workflow for turning vague failures into precise symptoms, testable hypotheses, useful evidence, and fixes that address the cause.