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WeAreDevelopers LIVE • Dec 1, 2023

Fighting test flakiness with time machines

Filip Hric

Stop patching flaky tests with arbitrary wait commands. Start using time-travel debuggers to step backward through execution states. Eliminate end-to-end instability for good.

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#1 about 3 min

Introduction to time travel for debugging flaky tests

The concept of observing previous state helps diagnose unstable test automation scripts.

#2 about 4 min

Analyzing test automation challenges and the Cypress timeline

Using built-in timeline features to observe unpredictable state variations during test execution.

#3 about 4 min

Fixing timing issues in Cypress with guarding assertions

Adding explicit state expectations prevents failures caused by unpredictable application load speeds.

#4 about 7 min

Using Playwright Trace Viewer to debug unstable scripts

Generating and inspecting execution traces reveals hidden transitions and interaction failures.

#5 about 9 min

Uncovering application errors with the Replay browser

Capturing full runtime environments allows reverse debugging without modifying underlying source code.

#6 about 14 min

Integrating automated recordings to fix asynchronous state bugs

Examining network payloads within recorded tests reveals root causes of automation flakiness.

#7 about 6 min

Underlying architecture and adoption challenges of runtime capture

Forking the Chromium engine enables deep runtime visibility despite a steep usability learning curve.

#8 about 8 min

Managing continuous integration setups and white box strategies

Automated recording in pipelines securely captures runtime data while encouraging deeper code exploration.

Matching moments

2:45 min

Advantages of using Cypress for testing workflows

Anna Mcdougall · JS Congress

2:23 min

Keeping up with Web3 testing tools

Soumaya Erradi · LIVE

2:50 min

Introduction to end-to-end testing with Cypress

Soumaya Erradi · LIVE

2:00 min

The software testing timeline and regression checking pitfalls

Ingo Philipp · LIVE

7:11 min

Identifying root causes of flaky testing and false negatives

Ramona Schwering Ramona Schwering · LIVE

3:01 min

Exploring the expansion of end-to-end testing utility suites

Daniel Afonso Daniel Afonso · World Congress 2025

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September 25, 2026 · 13:30–14:00

Stage 7

Agents Can't Iterate Against Tests That Lie

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Open session

World Congress 2026 North America

September 25, 2026 · 14:10–14:40

Stage 7

Why Your iOS App Feels Broken After an Hour: Diagnosing Long-Session Performance on Real Devices

Vasuki Uday Kiran Vudathala

Staff Performance Engineer at ServiceNow

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Open session

World Congress 2026 North America

September 24, 2026 · 16:10–16:40

Stage 1

Closing the autonomous software development loop

Justin Halsall

Core Team Maintainer and CEO at rrweb

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Open session

World Congress 2026 North America

September 24, 2026 · 11:40–12:10

Stage 4

Taming Rogue Agents: Observability-Driven Evaluation for Production Reliability

Anagha Rumade, Anjana Umapathy, Apoorva Jaiswal

Anagha Rumade
Anjana Umapathy
Apoorva Jaiswal
Open session

World Congress 2026 North America

September 24, 2026 · 14:10–14:40

Stage 9

One Repo, One Strategy: Scalable Full-Stack Testing in a Monorepo World

Bartosz Leczycki, Paweł Matynia

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Open session

World Congress 2026 North America

September 25, 2026 · 16:50–17:20

Stage 3

Your Evals Passed. Your Agent Just Emptied a Database.

Tejas Pravinbhai Patel

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