@s-molinari after upgrading quasar, creating a new project using the CLI with quasar create project-name, gives an option for composition api components.

And I was wrong in my initial post: you can just enable composition api via boot files.

Here’s the boot file I’m now using:

// composition-api.js
import VueCompositionApi from '@vue/composition-api';
import { boot } from 'quasar/wrappers';

export default boot(({ Vue }) => {
  Vue.use(VueCompositionApi);
});

Nevermind, found the new starter kit with composition api in discord.

Is there any way to enable the new composition API? It must be imported before App.vue, such as

import Vue from 'vue'
import VueCompositionApi from '@vue/composition-api'

// Register the Composition API plugin BEFORE you import App.vue
Vue.use(VueCompositionApi)

import App from './App.vue'

Unfortunately, boot files did not work for this because in the generated client-entry.js, they are imported immediately after app.js (and therefore App.vue).