astro/packages/integrations/image/test/fixtures/assets-prefix/astro.config.mjs

import { defineConfig } from 'astro/config';
import image from '@astrojs/image';

// https://astro.build/config
export default defineConfig({
	integrations: [image()],
	build: {
		assetsPrefix: 'http://localhost:4321',
	}
});