A flaky app will lead to flaky tests. Learn how time-travel debugging can reveal the root cause of instability, not just patch the symptoms.
#1about 3 minutes
The high cost of debugging flaky tests
Test flakiness is a major time sink in development, with debugging often taking longer than writing the tests themselves.
#2about 6 minutes
Debugging a race condition with the Cypress timeline
Use the Cypress timeline to inspect the DOM state at different points in time and diagnose a flaky test caused by a race condition.
#3about 6 minutes
Using Playwright's Trace Viewer for similar insights
Playwright's Trace Viewer provides a time-travel debugging experience similar to Cypress, which is especially valuable for analyzing test failures in CI environments.
#4about 2 minutes
Shifting focus from fixing the test to fixing the app
Testers often instinctively try to fix a flaky test with waits or retries, but the more robust solution is often to fix the underlying instability in the application itself.
#5about 3 minutes
Introducing Replay.io with a manual recording demo
Replay.io is a browser that records everything, allowing you to retroactively add print statements and use a time-travel debugger to inspect application state.
#6about 13 minutes
Integrating Replay.io with Cypress to debug an API race condition
By integrating Replay.io into a Cypress test suite, you can analyze the full application runtime, including internal state and network calls, to find the root cause of flakiness.
#7about 4 minutes
Fixing the application to resolve test flakiness
Fixing an API race condition by disabling a UI element until the necessary data has loaded makes the application more stable and eliminates the need for artificial waits in the test.
#8about 13 minutes
Q&A on Replay.io architecture, adoption, and CI/CD
The speaker answers questions about Replay.io's technical foundation, its integration with CI/CD pipelines, and strategies for handling sensitive data during recordings.
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