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
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
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
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
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
Testing
Progressive delivery is the practice of gradually rolling out changes to users while automatically verifying that the release meets your quality standards at each step. Flagger is a Kubernetes operator that automates this process — it manages canary deployments, traffic mirroring, and A/B testing with automated analysis and rollback. Unlike
Deployment Testing
Feature flags (also called feature toggles or feature switches) are one of the most powerful tools in a modern engineering team's toolkit. They decouple deployment from release, let you test features in production with controlled rollouts, and enable instant kill switches when something goes wrong. But feature flags
Testing
A charter is the heart of structured exploratory testing. It defines what you're testing and why — without prescribing how. A debrief closes the loop, turning a tester's observations into shared knowledge. These two practices — charter writing and debriefing — are what separate disciplined exploratory testing from undirected
Testing
A/B testing and canary deployments both route subsets of users to different versions of your software. Both involve traffic splitting. Both let you compare two variants. But they solve fundamentally different problems and require different tooling, team involvement, and success criteria. Confusing the two leads to misapplied techniques: running