Latest stories from ShopperCove

Should You Leave Jest for Vitest? 2.0s vs 1.3s

Jest 30.5.2 vs Vitest 5.0.3 on 40 files / 200 Node tests: wall medians Jest 2027 ms, Vitest isolate-on 2422 ms, Vitest --no-isolate 1287 ms, Jest --runInBand 3346 ms. Both 200/200 pass. Leave Jest after measuring isolate; default isolate can lose.

5 Oct 20265 min read

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Latest stories from ShopperCove

Should You Leave Jest for Vitest? 2.0s vs 1.3s

5 Oct 20265 min read

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Should You Leave Prettier? 1.59s vs 0.51s

dprint 0.60.1 vs Prettier 3.9.9 on 180 files (120 JS + 40 JSON + 20 MD, 38925 B pristine): write medians 514 ms vs 1586 ms; check 455 ms vs 1313 ms. Output 44805 vs 45285 B. All 120 JS files differed on arrow-param parentheses under these defaults.

5 Oct 20265 min read

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Should You Leave PostCSS? 3ms vs 106ms

Lightning CSS 1.33.0 vs PostCSS 8.5.29 + Autoprefixer 10.6.1 + cssnano 6.1.2 on a 76,864-byte CSS fixture: medians 3.16 ms vs 105.75 ms (~33x). Outputs 70498 vs 68474 B. Leave Autoprefixer+cssnano-only stacks for Lightning; keep PostCSS for plugins Lightning does not replace.

5 Oct 20264 min read

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Should You Leave Terser? 824ms vs 41ms

Terser 5.51.2 vs esbuild 0.28.2 vs SWC 1.16.13 minify on a 403,418-byte unminified ESM bundle (800 modules): medians 824 ms / 41 ms / 70 ms. Output sizes 219492 / 207619 / 199712 B. Leave Terser if you only need fast minify; keep it for Terser-only compress options.

5 Oct 20265 min read

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tsx vs ts-node: Which Should You Use? 0.49s vs 1.18s

tsx 4.23.15 vs ts-node 10.9.2 on TypeScript 5.9.2 for a 50k-row script: medians 0.49 s vs 1.18 s (typecheck) vs 0.38 s (--transpile-only) vs 0.13 s precompiled node. TypeScript 7.0.2 crashes ts-node 10.9.2; tsx runs. Who should switch.

5 Oct 20264 min read

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Should You Leave Babel for SWC? 1.05s vs 46ms

Babel 8.0.6 vs SWC 1.16.13 vs esbuild 0.28.2 per-file transform on 501 TSX files (526 KB): medians 1.05 s / 46 ms / 83 ms. esbuild bundle of same entry 40 ms. Sample Comp0.js sizes close (1089/1121/1167 B). Leave Babel if you only strip TS/JSX; keep it for macros/unported plugins.

5 Oct 20265 min read

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Rspack vs Webpack: Which Builds Faster? 0.54s vs 4.3s

Rspack 2.2.8 vs Webpack 5.111.1 on a 201-module React fixture: cold production medians 0.54 s vs 4.33 s (~8.0x). Webpack+Babel vs Rspack+builtin:swc-loader. Raw bundles 174 KB vs 365 KB; gzip ~48 KB vs ~52 KB.

5 Oct 20265 min read

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Biome vs ESLint: Should You Switch? 0.41s vs 18.7s

Biome 2.5.15 check vs ESLint 9.39.4 + Prettier 3.8.4 on react-hook-form (317 files): 0.41 s vs 18.7 s sequential stack (ESLint 13.58 s, Prettier check 5.22 s). migrate eslint: 54/476 direct, ~50% covered. Biome 200 errors/427 warnings vs ESLint 0/562; 9 format diffs; 287 noExplicitAny from recommended.

5 Oct 20266 min read

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oxlint vs ESLint: Is 100x Faster Worth It?

oxlint 1.87.0 vs ESLint 9.39.4 on react-hook-form (301 files): 0.09 s vs 9.81 s single-thread (6.02 s with --concurrency auto, 1.10 s warm --cache). @oxlint/migrate ported 42 of 84 rules natively, 80 with JS plugins. 315 vs 562 warnings; seeded test 11/15 native, 13/15 with JS plugins, ESLint 15/15.

5 Oct 20267 min read

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pnpm vs npm vs Bun: Which Installs Fastest? 14s, 3.1s, 1.5s

npm 12.2.0 vs pnpm 12.9.1 vs Bun 1.4.2 on one 24-dependency React + Vite app: from scratch 14.2 s / 3.1 s / 1.5 s; lockfile + warm cache 2.9 s / 0.28 s / 0.27 s; lockfile + empty cache 3.9 s / 2.3 s / 0.45 s. Disk, lockfile size and the pnpm phantom-dependency catch.

5 Oct 20267 min read

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jsdom vs happy-dom: Should You Switch? 1.9x Faster, 2 Gaps

jsdom vs happy-dom decision with ShopperCove timing in Vitest 5.0.3: 20-file / 60-test suite median 1.65 s on happy-dom 20.14.5 vs 3.11 s on jsdom 30.1.2; heavy DOM 1.33 s vs 1.81 s (jsdom 29.1.1 2.55 s). Compat 8/8 jsdom 30, 6/8 happy-dom, 5/8 jsdom 29.

5 Oct 20266 min read

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TypeScript 7: Is tsc Really 7x Faster?

TypeScript 7 upgrade decision with ShopperCove timing on Hono (906 files): median 10.23 s on 6.0.3 vs 1.41 s on 7.0.2 (7.3x), peak RSS 1,032 MB vs 718 MB, plus 2 moved @ts-expect-error targets and the typescript-eslint <6.1 peer limit.

5 Oct 20267 min read

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