Automated regression testing: A complete introduction

Automated regression testing verifies that software hasn't reverted to a broken state after changes. Manual regression testing is slow, error-prone, and costly, making automation essential. Existing unit and integration tests already serve as regression tests. Key best practices include using test management tools, maintaining a testing schedule, writing failing tests for new bugs, categorizing tests, keeping suites up to date, and integrating tests into CI/CD pipelines. Common challenges include test maintenance burden, fragile tests, long execution times, and environment inconsistency. A risk-based approach is recommended when starting out, and slower tests (like E2E) should run less frequently than fast unit tests.