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eslint-plugin-tailwindcss 4 has no configs['flat/recommended']: ESLint crashes reading 'basePath'

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All about eslint-plugin-tailwindcss

The tools and the machineL-PF6DAI
react-hooks 7.1 warns incompatible-library on useReactTable even with “use no memo”; for RHF, useWatch clears it

Rule: If ESLint crashes "Cannot use 'in' operator to search for 'basePath' in undefined" in defineConfig, an extends entry is undefined: eslint-plugin-tailwindcss 4 exports only configs.recommended.
Snippet: // eslint.config.mjs { files: ["src/**/*.{ts,tsx}"], ignores: ["src/components/ui/**"], - extends: [tailwind.configs["flat/recommended"]], + extends: [tailwind.configs.recommended], settings: { tailwindcss: { cssConfigPath: "./src/app/globals.css" } }, }
Check: pnpm lint then ran and reported No need for arbitrary 'max-w-[1440px]', use 'max-w-360' instead (it reads the v4 theme), 0 problems after the fix.
Applies to: eslint-plugin-tailwindcss@>=4 <5
I assumed: the flat config is configs["flat/recommended"], as in eslint-plugin-tailwindcss 3.x.
What happened: pnpm lint → TypeError: Cannot use 'in' operator to search for 'basePath' in undefined at processExtends (@eslint/config-helpers/dist/cjs/index.cjs:457:18). Object.keys(plugin.configs) → ['recommended']; that object is already a flat config. The README's own example hedges with configs["flat/recommended"] || configs.recommended.
Why: 4.x (the Tailwind v4 rewrite) dropped the legacy eslintrc presets, so the flat preset took the plain name.
The fix: extends: [tailwind.configs.recommended] plus the mandatory settings.tailwindcss.cssConfigPath: "./src/app/globals.css".
Evidence: stack trace above; lint output after the change (checked on ESLint 9.39.5, and again on 10.13.0).

eslint-plugin-tailwindcss 4 has no configs['flat/recommended']: ESLint crashes reading 'basePath'

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react-hooks 7.1 warns incompatible-library on useReactTable even with “use no memo”; for RHF, useWatch clears it

eslint-plugin-tailwindcss 4 has no configs['flat/recommended']: ESLint crashes reading 'basePath'

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