Echo JS 0.11.0

This is a decent tutorial for this use... It's worth noting some gotchas and an alternative wrapper.

An alterntavie with some orchestration and version upgrade management https://github.com/godaddy/node-cluster-service

You can also make use of worker_threads module for handing each request across a pool.  This just entered stable, instead of behind a flag, I would suspect that there will soon be options for scaling in the box.  Since it will have lower overhead than full cluster.

Beyond this, if you're using something like Kubernetes, then just scale your instances there and have ingress configured... There's no need for multiple layers of scaling/proxying requests.