ckeditor5-1.0.x-dev/js/admin/vite.config.js

import vue from '@vitejs/plugin-vue'
const path = require('path')

/**
 * https://vitejs.dev/config/
 * @type {import('vite').UserConfig}
 */
export default {
  plugins: [vue()],
  build: {
    lib: {
      entry: path.resolve(__dirname, 'src/main.js'),
      name: 'CKEditor5Admin',
      formats: ['umd']
    },
    rollupOptions: {
      external: ['sortablejs'],
      output: {
        file: '../build/admin/admin.js',
        dir: null,
        format: 'umd',
        globals: {
          sortablejs: 'Sortable'
        },
        name: 'CKEDITOR5_ADMIN'
      },
    }
  }
}