$ man build-process

Build Process

The steps that transform your source code into the final website visitors see.

Next.js apps need to be compiled. TypeScript needs to convert to JavaScript. Dependencies need to be installed. The build process does all of this. If the build fails, your deploy fails.

Locally, npm run dev builds in development mode with hot reload. On Vercel, the build happens automatically on every push. Check build logs if it fails.