diagnose

To debug intermittent failures, you build a deterministic reproduction loop, rank likely causes, probe variables one at a time with targeted instrumentation, and verify the fix with a regression test.

Root cause analysis for a performance regression involves creating a minimized reproduction harness, testing hypotheses methodically using bisection, and confirming the slowdown is eliminated through deterministic verification.

Isolate hard bugs by narrowing the problem space with replay harnesses, CLI checks, or HTTP requests, applying targeted probing instead of noisy logging to capture the exact failure signal.

You need targeted instrumentation when debugging hard bugs requiring hypothesis testing, allowing you to probe specific variables one at a time and capture deterministic failure signals without noisy log output.

Yes, bisection is applied to track down slowdowns and regressions by systematically narrowing the problem space, testing hypotheses against a fast reproduction loop, and isolating the specific change causing the failure.

After locking in the fix with a regression test and confirming the original bug no longer reproduces, you clean up all temporary debug work and instrumentation to restore the system to its original state.