Fixes for the errors developers are searching for, each one reproduced on a real machine first, plus hands-on tests of AI and dev tools. By Nilay Kabariya.https://nilaykabariya.blogenhttps://nilaykabariya.blog/fixes/vite-failed-to-resolve-import-aliashttps://nilaykabariya.blog/fixes/vite-failed-to-resolve-import-aliasVite can't find an @/ import until the alias is in vite.config. Why tsconfig paths alone don't help, and the new Vite 8 Rolldown wording. Reproduced.Tue, 22 Sep 2026 00:00:00 GMTvitejavascripttypescripthttps://nilaykabariya.blog/fixes/tailwindcss-directly-as-postcss-pluginhttps://nilaykabariya.blog/fixes/tailwindcss-directly-as-postcss-pluginTailwind CSS v4 moved its PostCSS plugin to a separate package. The two-line change to postcss.config.js, reproduced and verified.Tue, 22 Sep 2026 00:00:00 GMTtailwindpostcsscsshttps://nilaykabariya.blog/fixes/tailwind-cannot-apply-unknown-utility-classhttps://nilaykabariya.blog/fixes/tailwind-cannot-apply-unknown-utility-classTwo causes trigger this Tailwind v4 error: an unmapped theme variable (border-border) or a CSS file missing @reference. Both reproduced and fixed.Tue, 22 Sep 2026 00:00:00 GMTtailwindcssshadcnhttps://nilaykabariya.blog/fixes/npx-tailwindcss-init-could-not-determine-executablehttps://nilaykabariya.blog/fixes/npx-tailwindcss-init-could-not-determine-executableTailwind CSS v4 removed the init command, so npx has nothing to run. Two fixes, both reproduced: set up v4 without a config file, or pin v3.Tue, 22 Sep 2026 00:00:00 GMTtailwindnpmcsshttps://nilaykabariya.blog/fixes/npm-eresolve-unable-to-resolve-dependency-treehttps://nilaykabariya.blog/fixes/npm-eresolve-unable-to-resolve-dependency-treenpm refuses to install a package whose peer range doesn't include your React version. Four fixes compared, and why --legacy-peer-deps alone breaks later.Tue, 22 Sep 2026 00:00:00 GMTnpmreactdependencieshttps://nilaykabariya.blog/fixes/err-require-esm-require-of-es-modulehttps://nilaykabariya.blog/fixes/err-require-esm-require-of-es-moduleWhy require() of an ES module fails, why it mostly stopped failing on Node 22.12+, and the new errors you hit instead. All reproduced on Node 24.Tue, 22 Sep 2026 00:00:00 GMTnodeesmcommonjshttps://nilaykabariya.blog/fixes/err-ossl-evp-unsupported-digital-envelope-routineshttps://nilaykabariya.blog/fixes/err-ossl-evp-unsupported-digital-envelope-routinesOld webpack 4 builds crash on Node 17+ with 0308010C. Upgrading webpack 4 to 4.47.0 fixes it without the legacy OpenSSL flag. Reproduced on Node 24.Tue, 22 Sep 2026 00:00:00 GMTwebpacknodeopensslhttps://nilaykabariya.blog/fixes/eaddrinuse-address-already-in-use-windowshttps://nilaykabariya.blog/fixes/eaddrinuse-address-already-in-use-windowsYour Node dev server won't start because the port is taken. Find the process holding it, stop it, and restart. Every step reproduced on Windows 11.Tue, 22 Sep 2026 00:00:00 GMTnodewindowsdevserverhttps://nilaykabariya.blog/fixes/dirname-is-not-defined-in-es-module-scopehttps://nilaykabariya.blog/fixes/dirname-is-not-defined-in-es-module-scopeES modules don't have __dirname or __filename. The one-line modern fix (import.meta.dirname) and the fallback for older Node, both run on Node 24.Tue, 22 Sep 2026 00:00:00 GMTnodeesmjavascripthttps://nilaykabariya.blog/fixes/cannot-use-import-statement-outside-a-modulehttps://nilaykabariya.blog/fixes/cannot-use-import-statement-outside-a-moduleThe fix for Node and the browser. On Node 24 a plain .js file now often just works, so here's exactly when the error still happens. Reproduced in both.Tue, 22 Sep 2026 00:00:00 GMTnodeesmjavascript