Resolving Type Mismatch in Config Module with Effect

import { Config, Effect } from "effect";

const appConfig = Config.all({
  host: Config.string("HOST").pipe(Config.withDefault("localhost")),
  port: Config.number("PORT").pipe(Config.withDefault(8080)),
});

const config = Config.all({
  app: appConfig,
});

type ConfigType = Config.Config<typeof config>;

// function to load the configuration
async function loadConfig(): Promise<ConfigType> {
  return await Effect.runPromise(config); // lint error under 'return'
}

const cfg = await loadConfig();
console.log(cfg);
console.log(cfg.app.port);