Runtime error on Vercel with Nitro: "Class extends value undefined"
Deploying Start + Nitro to Vercel, getting this in the router
bundle at runtime (works locally):
Class extends value undefined is not a constructor or null
Seems like a Zod version conflict -
router-plugin/start-plugin-core need zod 3, but better-auth
pulls in zod 4 via transitive dep.
Tried:
- Downgrading better-auth to 1.2.9 (last zod 3 version)
- Pinning better-call to 1.1.0 via overrides (before it added
zod 4 peer dep)
- rm -rf node_modules in Vercel build command
- Force redeploy with cache cleared
Local build outputs different bundle hash than what Vercel
serves, even after cache clear. Anyone hit this with Start +
Nitro on Vercel?
bundle at runtime (works locally):
Class extends value undefined is not a constructor or null
Seems like a Zod version conflict -
router-plugin/start-plugin-core need zod 3, but better-auth
pulls in zod 4 via transitive dep.
Tried:
- Downgrading better-auth to 1.2.9 (last zod 3 version)
- Pinning better-call to 1.1.0 via overrides (before it added
zod 4 peer dep)
- rm -rf node_modules in Vercel build command
- Force redeploy with cache cleared
Local build outputs different bundle hash than what Vercel
serves, even after cache clear. Anyone hit this with Start +
Nitro on Vercel?
