Vercel INTERNAL FUNCTION NOT FOUND after migration

Published: May 15th, 2024

I recently moved this site from Vite based to NextJS and got the following error on a Vercel build:

INTERNAL_FUNCTION_NOT_FOUND

Something I had not seen was to update the Build & Development Settings under the Settings > General tab in my Vercel dashboard.

At first I had set up the project with Vite via Vercel and the Framework preset was still set to Vite so my project could build but not load any preview, resulting in the error message while trying to preview through the Github preview link.

All was fine locally, even the build function.