Blog

Fix `IntersectionObserver is not defined` in Jest by adding a clean global mock in `jest.setup.ts`. Includes TypeScript-safe setup and a test example.

Trigger a React error boundary reliably in browser and Jest tests. Covers render-time crashes, event-handler caveats, plus practical test patterns fast.

Pass GitLab CI variables safely to Ansible shell tasks with extra-vars and task-level environment. Also explains why `export` in one task is not persisted.

Enforce named functions inside useEffect for better debugging and stack traces.

Detect click outside a modal or dropdown using contains() method.

Fix the common TypeScript error when accessing event properties like target.value.

Fix the confusing TypeScript error when using useRef with proper type arguments.

Fix the 'window.matchMedia is not a function' error in Jest tests with a quick mock setup.

The z alias from zoxide doesnt work in non-interactive bash shells like cron jobs or tool subshells. Heres how to fix it with BASH_ENV.

Get a public HTTPS URL for your localhost in seconds using cloudflared quick tunnels. No account needed. Perfect for testing webhooks from GitHub, Slack, Stripe, or any third-party service.

Set up wildcard subdomains with Caddy and DigitalOcean using DNS challenge. Build Caddy with the DigitalOcean DNS module and serve subdomains over HTTPS.

Fix CORS errors in json-server with a custom server.js and middleware. Covers preflight OPTIONS requests and when to use wildcard vs specific origin.

How to securely connect to a PostgreSQL database running inside a Docker container on a remote server, using an SSH tunnel — no open ports required.

Quick setup guide to add Sequential Thinking MCP to Claude Code, verify it works, and fix common setup errors.

Simple guide to add Context7 MCP on Claude Code, check if it is active, and troubleshoot common install issues.

Discover 5 simple applications to enhance your JavaScript skills. Dive deeper into learning by trying out these JavaScript examples today!

Fix the "window.scrollTo is not a function" Jest error with a clean test setup mock and practical verification tips.

Resolve the 'ResizeObserver is not defined' error in Jest tests. Our guide shows how to mock ResizeObserver for hassle-free unit testing.

Set npm version tags without the default v prefix using one config line, with notes for CI and release flow.

Practical ways to print GitLab CI environment variables safely for debugging without leaking sensitive secrets.

Simple way to test Next.js Image in Jest by mocking it as a plain img tag, plus checks and common mistakes.

Simple way to test next-i18next in Jest by mocking translation hooks so component tests stay focused and stable.

Fix Jest "Cannot use import statement outside a module" when mocking Swiper by adjusting transformIgnorePatterns.

Fix Jest EMFILE too many open files error with practical config changes, watcher tips, and stable CI settings.

Mock Next.js useRouter in Jest with reliable patterns for pathname, query, and push assertions in component tests.

Fix the OpenSSL digital envelope routines unsupported error on Apple Silicon with safe Node/OpenSSL workarounds.

Change a feature branch base cleanly with git rebase --onto, plus safe checks to avoid losing work.

Fix ENOSPC file watcher limit error on Linux when running Next.js, Vite, or Jest with practical commands and checks.

Easily start node project by using nodemon and babel

How to keep only specific Moment.js locales in Webpack to reduce bundle size and avoid loading every locale.

How to find exactly where window.scrollTo is being called in tests using spies, stack traces, and quick debug steps.