Filip Hric

Fighting test flakiness with time machines

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.

Fighting test flakiness with time machines
#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.

Related jobs
Jobs that call for the skills explored in this talk.

test

Milly

Milly
Vienna, Austria

Intermediate
.NET
TypeScript
+1

test

Milly

Milly
Vienna, Austria

Intermediate
.NET
TypeScript
+1

Matching moments

How to manage flakiness from dynamic content
09:25 MIN

How to manage flakiness from dynamic content

Let's get visual - Visual testing in your project

Managing flakiness from dynamic content and loading
05:33 MIN

Managing flakiness from dynamic content and loading

Let's get visual - Visual testing in your project

Understanding end-to-end testing and the benefits of Cypress
03:54 MIN

Understanding end-to-end testing and the benefits of Cypress

Watch Tests Go Brrrr! : Getting Started with Cypress in ReactJS

Q&A on scaling tests and choosing frameworks
16:15 MIN

Q&A on scaling tests and choosing frameworks

Let's get visual - Visual testing in your project

Creating more time for valuable exploratory testing
02:54 MIN

Creating more time for valuable exploratory testing

How to add test automation to your project: The good, the bad, and the ugly

Using end-to-end tests for performance monitoring
04:16 MIN

Using end-to-end tests for performance monitoring

Measure and improve frontend performance by using test automation

The evolution of testing practices at Chrono24
01:45 MIN

The evolution of testing practices at Chrono24

Write tests you love, not hate

Audience Q&A on testing strategies
08:48 MIN

Audience Q&A on testing strategies

Yes, You Need to Unit Test your JavaScript. Here's How.

Featured Partners

Related Videos

See all videos
Let's get visual - Visual testing in your project54:23

Let's get visual - Visual testing in your project

Ramona Schwering

Write tests you love, not hate56:49

Write tests you love, not hate

Jens Happe

The 2025 State of JavaScript Testing28:33

The 2025 State of JavaScript Testing

Daniel Afonso

Watch Tests Go Brrrr! : Getting Started with Cypress in ReactJS53:45

Watch Tests Go Brrrr! : Getting Started with Cypress in ReactJS

Anna McDougall

Let's get visual - Visual testing in your project44:59

Let's get visual - Visual testing in your project

Ramona Schwering

How To Test A Ball of Mud42:34

How To Test A Ball of Mud

Ryan Latta

Frontend Performance Testing in practice36:50

Frontend Performance Testing in practice

Jonas Kröger

How not to test 43:07

How not to test

Golo Roden

Related Articles

View all articles
EM
Eli McGarvie
Stop Wasting Time: How to Lead a Stand-Up Meeting & Get Results
We all know the feeling: your stand-up meeting starts… and the energy in the room slowly deflates. Eyes glaze over, minds wander. Maybe you can even see their attention drop on smartphones or laptops.Within minutes or even seconds, instead of a quick...
Stop Wasting Time: How to Lead a Stand-Up Meeting & Get Results
CH
Chris Heilmann
WeAreDevelopers LIVE days are changing - get ready to take part
Starting with this week's Web Dev Day edition of WeAreDevelopers LIVE Days, we changed the the way we run these online conferences. The main differences are:Shorter talks (half an hour tops)More interaction in Q&AA tips and tricks "Did you know" sect...
WeAreDevelopers LIVE days are changing - get ready to take part

From learning to earning

Jobs that call for the skills explored in this talk.