HonoH
Hono•4mo ago
shadow

[Vercel] ERR_MODULE_NOT_FOUND on deploy but works locally

Hey everyone 👋

I’m running into an issue when deploying my Hono app to Vercel. Locally, the app builds and runs fine (bun build && bun start works with no errors). But on Vercel, the build passes, then on start I get this error:

Error [ERR_MODULE_NOT_FOUND]: Cannot find module '/var/task/apps/server/src/lib/auth' imported from /var/task/apps/server/src/index.js
    at finalizeResolution (node:internal/modules/esm/resolve:281:11)
    at moduleResolve (node:internal/modules/esm/resolve:866:10)
    at moduleResolveWithNodePath (node:internal/modules/esm/resolve:990:14)
    at defaultResolve (node:internal/modules/esm/resolve:1033:79)
    at ModuleLoader.defaultResolve (node:internal/modules/esm/loader:780:12)
    at #cachedDefaultResolve (node:internal/modules/esm/loader:704:25)
    at ModuleLoader.resolve (node:internal/modules/esm/loader:687:38)
    at ModuleLoader.getModuleJobForImport (node:internal/modules/esm/module_job:305:38)
    at ModuleJob._link (node:internal/modules/esm/module_job:137:49) {
  code: 'ERR_MODULE_NOT_FOUND',
  url: 'file:///var/task/apps/server/src/lib/auth'
}
Node.js process exited with exit status: 1


Things I’ve checked:
  • The file exists at apps/server/src/lib/auth.ts.
  • It runs locally without errors.
  • The error only happens in the Vercel runtime after deploy.
Was this page helpful?