The vercel build command can be used to build a project locally or in your own CI environment. Build artifacts are placed into the .vercel/output directory according to the Build Output API.
When used in conjunction with the vercel deploy --prebuilt command, this allows a Vercel Deployment to be created without sharing the Project's source code with Vercel.
Check out the documentation for more information.
vercel build && vercel deploy --prebuilt