Testing
The best way to learn TDD is to do it, not read about it. This tutorial walks through a complete TDD session in JavaScript using Jest. We will build a password validator from scratch — no implementation code until the tests demand it. By the end, you will have a fully
Testing
TDD is easy to practice on a greenfield project. You start from nothing, write the test, write the code, and the cycle works exactly as described in the textbooks. Legacy code is different. The code already exists. It was written without tests. It has dependencies that are hard to isolate,
Testing
Picking a synthetic monitoring tool is a decision most teams make once and live with for years. The difference between the right tool and the wrong one is often less about features and more about fit: what kind of engineers use it, what else it integrates with, and what it
Testing
Synthetic monitoring and real user monitoring (RUM) both answer the question "is my application working?" — but they answer it differently, from different angles, with different tradeoffs. Most teams need both. The question is understanding what each one tells you. What Each One Is Synthetic monitoring runs scripted tests
Testing
Playwright is one of the best tools for synthetic monitoring of web applications. It's fast, it supports all major browsers, it handles modern JavaScript applications well, and its API is intuitive enough that you can write a useful monitor in 20 minutes. This guide covers how to structure
Testing
You've deployed to production. The deployment logs say success. The pod is running. The load balancer shows healthy. Everything looks fine. But "looks fine" and "works correctly" are different things. Production deployments fail in ways that staging doesn't predict: environment variable differences,
Testing
Most smoke test suites fail in one of two ways. Either they're so minimal they miss real problems, or they've grown into a 45-minute regression suite that nobody calls "smoke" with a straight face anymore. Designing a good smoke test suite requires making deliberate
Testing
A regression test suite that nobody maintains is a liability, not an asset. After six months of neglect, you'll have 30% of tests failing for no good reason, developers who've learned to ignore failures, and zero confidence in your "green" builds. This is test
Testing
"Regression testing" and "retesting" get used interchangeably in engineering conversations, but they're different activities with different goals, different triggers, and different scopes. Mixing them up leads to either missed bugs or wasted effort. Here's a clear breakdown. The Short Version Retesting: You
Testing
A regression test suite that runs once a week on a developer's laptop isn't regression testing — it's wishful thinking. Real regression testing happens automatically, on every meaningful code change, as part of your CI/CD pipeline. Here's how to set that up
Testing
Playwright has become the go-to tool for browser-based regression testing. It's fast, reliable, and supports Chromium, Firefox, and WebKit out of the box. This tutorial walks through setting up a practical regression test suite with Playwright — from project structure to CI integration. Why Playwright for Regression Testing Playwright
Testing
Running your entire regression suite on every commit is a solved problem — it's just slow and expensive. The real challenge is figuring out which tests to run when, so you catch regressions as early as possible without waiting two hours for CI. AI-powered test selection is changing this