import { config } from '$deno/dotenv/mod.ts';

const env = await config();
Object.keys(env).forEach(key => Deno.env.set(key, env[key]));

await import('./main.ts');

main.ts

import { webServe } from 'https://deno.land/x/deno_web_serve/mod.ts';

await webServe();

/public/index.html

<html>
    ...
    <!-- SCRIPT_ENVS -->
    <script type="text/javascript" src="/bundle.js"></script>
    <!-- SCRIPT_FOOTER -->
</html>