debugging

Finds the root cause of failures in any language with a reproduce, hypothesize and prove method, using The Pragmatic Programmer. Use whenever behavior is wrong and the cause is unknown: a stack trace, a bug report, a crash or hang, an intermittent or flaky failure, something broken only in production, a fix that didn't hold, or someone stuck on an error, even if they only paste the message. Covers "por qué falla", "no entiendo este error", "falla a veces", "arreglá este bug" and "en mi máquina anda". Not needed when the cause is already evident from the error; for writing regular tests use testing; to add logging or retries use production-readiness.