[winrid]

That doesn't sound right.

Do data dump from prod for initial sync and then setup replication from RDS to new cluster. Once synced do switch. Then you're off RDS and can shard on Citus.

[djtango]

a) they didn't want to move off RDS b) this is a pretty big hand wave over migrating your persistence store on a moving product and moving engineering teams

The coordination alone usually takes months

[winrid]

Yes, it takes months. They also spent months building this custom solution that they now need to maintain.

[raverbashing]

Yes but they probably wouldn't want to migrate off RDS.

[nathanappere]

This doesn't work with the constraint of "staying on AWS" though.

[winrid]

Yes it does.