Understanding a Real Use Case example of `Runtime`

const layer = EmailService.EmailServiceLive;

const runtimeEffect = Effect.gen(function* (_) {
  const scope = yield* _(
    Scope.make(ExecutionStrategy.parallel).pipe(
      Effect.tap((scope) =>
        Scope.addFinalizer(scope, Console.log("finalizer 1"))
      ),
      Effect.tap((scope) =>
        Scope.addFinalizer(scope, Console.log("finalizer 2"))
      )
    )
  );

  const runtime = yield* _(Layer.toRuntime(layer), Scope.extend(scope));

  yield* _(Scope.close(scope, Exit.unit));
  return runtime;
});

export async function runPromise<E, A>(
  effect: Effect.Effect<Layer.Layer.Success<typeof layer>, E, A>
): Promise<A> {
  const runtime = await Effect.runPromise(runtimeEffect);
  return Runtime.runPromise(runtime)(effect);
}