Test Automation
A/B testing (split testing) lets you run controlled experiments — showing variant A to one group and variant B to another — to measure which performs better. From an engineering perspective, the challenge is not the statistics but the testability: experiments must be deterministic, isolated, and not interfere with your automated
Testing
Exploratory testing doesn't require specialized tools — a text editor and a bug tracker will do. But the right tools reduce friction between testing and documentation, helping testers capture observations in real time without losing focus on the software under test. This guide covers the main categories of exploratory
Testing
Exploratory testing is powerful, but it has a management problem: how do you measure coverage, report progress, or coordinate across a team when tests aren't written in advance? Session-Based Test Management (SBTM) solves this by adding structure to exploratory testing without eliminating its flexibility. Developed by James and
Testing
Exploratory testing is simultaneous learning, test design, and test execution. Instead of following a predetermined script, the tester investigates the software using their knowledge, intuition, and structured heuristics to discover unexpected behavior. The term was coined by Cem Kaner in 1984, but the approach has become increasingly relevant as software
Testing
Agile development moves fast. Features land in sprints, not multi-month waterfall phases, and testing has to keep pace. Exploratory testing fits agile well — it's faster than scripted testing, catches bugs that scripts miss, and adapts to rapidly changing requirements. But making it work inside a sprint requires a
Testing
Canary deployments reduce release risk by routing a small percentage of production traffic to the new version before rolling it out fully. If the canary behaves badly — error rates spike, latency increases, business metrics drop — you roll back with minimal user impact. Argo Rollouts is the most capable Kubernetes-native tool
Testing
Design systems are the foundation of consistent UI. A broken button component or incorrect token in your design system affects every product that consumes it. Testing a design system requires more rigor than testing a single application — components must work correctly across all their states, variants, themes, and accessibility requirements.
Testing
Storybook interaction testing lets you simulate user behavior directly inside your stories — clicks, typing, keyboard navigation — and assert the results. Since Storybook 8, all of this runs through the @storybook/test package, which provides a unified API built on top of Testing Library and Vitest. This guide covers everything you
Testing
Both Storybook and Playwright can test UI components in a real browser. Both give you real DOM interaction, real CSS, and real browser behavior. But they approach component testing from different angles, and choosing the right one (or combining both) depends on your priorities. This guide compares Storybook and Playwright
Testing
Storybook 8 made component testing a first-class citizen. What was previously a documentation tool is now a full component testing platform — complete with built-in test runner, Vitest integration, and portable stories that run outside Storybook itself. This guide covers everything: setting up Storybook 8 for testing, writing stories that double
Testing
Visual regression testing catches unintended UI changes by comparing screenshots of your components against known-good baselines. Storybook + Chromatic is the most widely adopted setup for this: Storybook provides isolated component renders across all states, and Chromatic handles screenshot capture, diffing, and the review workflow. This guide covers everything from initial
Testing
Shadow testing (also called traffic mirroring or dark launching) sends a copy of real production requests to a new version of your service alongside the production version. The new version handles the request but its response is discarded — users only see the response from the stable version. This lets you