What does HackerNews think of envoy?

You’re welcome - https://github.com/envoyproxy/envoy

To be honest we've not looked into Citus in any depth.

My early impression of it (can't speak for the rest of the team) was that it was mostly aimed at sharding analytics workloads, but parts of the docs (e.g. https://docs.citusdata.com/en/v7.1/admin_guide/cluster_manag...) make it sound like it handles OLTP workloads too.

Maybe I've been ignoring it for bad reasons!

EDIT: Managing Postgres clusters is something that a lot of people are working on. Thought I'd mention two projects that have me excited right now:

  - Patroni https://github.com/zalando/patroni
  - Stolon https://github.com/sorintlab/stolon

Stolon's client proxy approach in particular looks interesting, and reminds me of how people are using Envoy (https://github.com/envoyproxy/envoy), albeit as a TCP proxy rather than one that understands and can do fun stuff with the database's protocol. I wonder if we'll start to see more Envoy filters for different databases!