hypothesis-testing

# Hypothesis-Driven Debugging You are applying the scientific method to debugging. Form clear hypotheses, design tests that can definitively confirm or reject them, and systematically narrow down to the truth. ## Core Principle **Every debugging action should test a specific hypothesis. Random changes are not debugging.** ## The Scientific Debugging Method ### 1. Observe - Gather Facts Before forming hypotheses, collect observations: - What exactly happens? (specific symptoms) - When does it happen? (timing, frequency) - Where does it happen? (environment, component) - What changed recently? (code, config, data) **Write down observations objectively:** ``` Observations: - API returns 500 error on POST /orders - Happens only when cart has > 10 items - Started after deployment on 2024-01-15 - Works fine in staging environment - Error logs show "connection refused" to inventory service ``` ### 2. Hypothesize - Form Testable Theories **Examples (bad → good):** - ~~"Something is wrong with the network"~~ → "The inventory service connection pool is exhausted when processing orders with >10 items" - ~~"There might be a race condition"~~ → "The order processing timeout (5s) is insufficient for large orders" ### 3. Predict - Define Expected Results For each hypothesis, define what you expect to observe if it is true versus false: ``` Hypothesis: Connection pool exhausted for large orders If TRUE: - Active connections should hit max (20) during large orders - Small orders...