𝗙𝗹𝗮𝗸𝘆 𝗧𝗲𝘀𝘁𝘀 𝗶𝗻 𝗟𝗮𝗿𝗮𝘃𝗲𝗹: 𝗪𝗵𝘆 𝗬𝗼𝘂𝗿 𝗖𝗜 𝗥𝗮𝗻𝗱𝗼𝗺𝗹𝘆 𝗙𝗮𝗶𝗹𝘀

𝗙𝗹𝗮𝗸𝘆 𝗧𝗲𝘀𝘁𝘀 𝗶𝗻 𝗟𝗮𝗿𝗮𝘃𝗲𝗹: 𝗪𝗵𝘆 𝗬𝗼𝘂𝗿 𝗖𝗜 𝗥𝗮𝗻𝗱𝗼𝗺𝗹𝘆 𝗙𝗮𝗶𝗹𝘀

Your tests pass locally. You rerun the pipeline. You change nothing. The tests fail again.

You have flaky tests.

These tests pass and fail without code changes. They destroy trust in your test suite. Developers ignore failures. They ship bugs to production.

Flaky tests come from these common causes:

• Time: Time logic is unstable. Use Carbon::setTestNow to fix the time.
• Database: Tests leak data. Use RefreshDatabase or DatabaseTransactions for isolation.
• Randomness: Random factory data causes fails. Define exact state in your factories.
• Queues: Async jobs are unpredictable. Use the sync driver or test the dispatch.
• Parallel Testing: Shared files create conflicts. Use Storage::fake for isolation.
• External APIs: APIs are slow or fail. Use Http::fake to mock responses.

The biggest risk is psychological. Teams stop trusting CI. Rerunning pipelines becomes a habit. Real bugs hide in the noise.

Stop rerunning your CI. Make your tests deterministic. A reliable suite produces the same result every time. Your workflow becomes faster and safer.

Source: https://dev.to/codecraft_diary_3d13677fb/flaky-tests-in-laravel-why-your-ci-randomly-fails-3m8n

Optional learning community: https://codecraftdiary.com/2026/05/09/how-mutation-testing-exposes-the-truth-php-2026-edition/