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Testing & QA

8 deep dives

Api Testing advanced

The Night Uber Scaled Tracing: Building a REST API Testing Framework That Survives 10,000+ Concurrency

Uber’s growth from roughly 500 microservices in 2015 to over 2,000 by 2017 created visibility blind spots across service...

postman rest-assured supertest

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Api Testing intermediate

The $2M Bug: How Stripe's Frontend Teams Broke Production and Fixed It Forever

It was 3am when Stripe's CEO got the call. Their payment processing API had changed, but frontend teams were still build...

wiremock mockserver msw

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Performance Testing intermediate

The 3am Pager: How We Broke the Internet (and Fixed It)

It was 3am when the pager went off. Our new feature had just gone viral, and instead of celebrating, we were watching ou...

jmeter k6 gatling

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Testing advanced

The $2 Million Bug: How DoorDash Tamed Distributed Transactions and Saved Their DashPass Launch

Picture this: DoorDash's engineers are staring at their monitors in horror. Their brand-new DashPass subscription servic...

api-testing database-testing mocking

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Performance Testing beginner

Latency Unmasked: How Flame Graphs Turn a Rails Delay Into a Playbook for Speed

It was a latency spike on Deliveroo's Rails endpoint used by riders to switch zones; requests pushed beyond 4 seconds an...

cpu-profiling memory-profiling flame-graphs

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E2e Testing advanced

When Chaos Teaches Resilience: Designing End-to-End Tests Across 100+ Data Centers

Picture this: a distributed streaming platform serving millions worldwide, and a single regional hiccup drums up a choru...

e2e-testing

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E2e Testing beginner

The 3am Pager: How I Learned to Stop Worrying and Love E2E Testing

It was 3am when the pager went off. The login form was broken in production, and our CEO had just tweeted about the new ...

e2e-testing

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Testing intermediate

The $2 Million Testing Mistake: How Stripe's API Meltdown Changed Everything

It was Black Friday, and Stripe's user creation API was failing spectacularly. Thousands of merchants couldn't process p...

testing

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