Your async tests pass 9 times out of 10 and fail in CI for no reason. The real bug is in how you test time-dependent code. Here is how to replace setTimeout with deterministic clocks, control promise ordering, and eliminate flakiness from every async test in your suite.
JavaScript Date is broken. Timezone bugs, daylight saving time surprises, and ambiguous date math cost teams hours every sprint. Here is how to use the Temporal API with the production-ready polyfill today, with patterns for timezone-aware scheduling, duration math, and calendar-safe date handling.
ESLint v9 makes flat config the default and deprecates .eslintrc. This is a breaking change in how you configure linting. Here is the migration path with a working config that covers TypeScript, React, imports, and Prettier integration.
Most devs reach for console.log when they should be using breakpoints, watch expressions, and conditional breakpoints. Here are the techniques that changed how I debug.
A practical comparison of the three major JavaScript runtimes: benchmark results, ecosystem maturity, and an honest recommendation for different use cases.
Most teams pick a JavaScript package manager based on what was popular when the project started. Five years later they're paying for that decision in install time and disk usage. Here is the honest comparison: pnpm's strict mode, yarn 4's feature parity, npm's recent improvements, and Bun's speed.
Node streams have a reputation as "advanced" and most developers avoid them. The truth is: streams are the right tool for two specific situations, and overkill for everything else. Here is the rule, the four-liner that handles most cases, and why async iterables are quietly killing the classic stream API.
Vite's dev experience is dramatically better than Webpack's: sub-second hot reloads versus 30 seconds. The migration is real work though, and not always worth it. Here is the realistic comparison, the migration patterns that succeed, and the cases where Webpack is still the right tool.
A default ESLint config has 80 rules and most of them are noise. The ones worth their CI cost catch real bugs: async without await, exhaustive switches, no-floating-promises. Here are the twelve I turn on for every TypeScript project, and the four I turn off because they cause more harm than good.