Tanstack Router + Vite race condition in filewatcher (EPERM)

Recently I got an issue when creating a new route using Tanstack Router + Vite

So by adding this config could solved the issue of EPERM: operation not permitted like below:

Error: EPERM: operation not permitted, rename 'D:IMTimt-fe.tanstacktmp884d3334-4715af826dad72bfa663dbba03a36060' -> 'D:IMTimt-fesrcroutesusers$phone_numberedit.tsx'
>     at file:///D:/IMT/imt-fe/node_modules/@tanstack/router-generator/dist/esm/generator.js:143:13
>     at async generate (file:///D:/IMT/imt-fe/node_modules/@tanstack/router-plugin/dist/esm/core/router-generator-plugin.js:39:4)
>     at async PluginContext.watchChange (file:///D:/IMT/imt-fe/node_modules/@tanstack/router-plugin/dist/esm/core/router-generator-plugin.js:49:4)
>     at async Promise.all (index 1)
>     at async EnvironmentPluginContainer.hookParallel (file:///D:/IMT/imt-fe/node_modules/vite/dist/node/chunks/node.js:29604:3)
>     at async EnvironmentPluginContainer.watchChange (file:///D:/IMT/imt-fe/node_modules/vite/dist/node/chunks/node.js:29771:3)
>     at async Promise.all (index 0)
>     at async onFileAddUnlink (file:///D:/IMT/imt-fe/node_modules/vite/dist/node/chunks/node.js:25530:3)

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By adding usePolling and stabilityThreshold props into vite.config.ts, the route creation happen like magic during development process (a bit slow but your server won’t shut)

vite.config.ts

const config = defineConfig({
  .... your other config ....
  // solves EPERM 
  server: {
    watch: {
      usePolling: true,
      interval: 300,
      awaitWriteFinish: {
        stabilityThreshold: 500,
        pollInterval: 100,
      },
    }
  }
})

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Note: This config doesn’t depend on specific OS/hardware settings. If you still encounter similar issues when generating multiple routes at once, simply increase the stabilityThreshold interval slightly (e.g., 500 → 800) as a further adjustment.