nextjs custom serve directory in production

Question

The problem: When I run next build on my production server, the page is served unstyled while building. What I want to do:

1. build the app to build directory
2. move build to build-public
3. serve the app from build-public.

I don't want to setup a custom server for that simple task.

My package.json scripts section:

"scripts": {
    "dev": "next dev -p 3002",
    "build": "next build",
    "start": "next start -p 3002"
  },

My next.config.js:

module.exports = {
  basePath: '',
  distDir: 'build', // build to build
  dir: 'build-public', // serve from build-public. 'Dir' option is not working.
}