next.js/examples/with-pretty-url-routing/routes.js

const UrlPrettifier = require('next-url-prettifier').default

const routes = [
  {
    page: 'index',
    prettyUrl: '/home'
  },
  {
    page: 'greeting',
    prettyUrl: ({lang = '', name = ''}) =>
      (lang === 'fr' ? `/bonjour/${name}` : `/hello/${name}`),
    prettyUrlPatterns: [
      {pattern: '/hello/:name', defaultParams: {lang: 'en'}},
      {pattern: '/bonjour/:name', defaultParams: {lang: 'fr'}}
    ]
  }
]

const urlPrettifier = new UrlPrettifier(routes)
exports.default = routes
exports.Router = urlPrettifier