out of interest, what columnstore indexes are available to postgres? Would be happy to find out that I'm missing something.

I know citus can provide columnar tables but I can't find columnar indexes for regular row-based tables in their docs. (use case of keeping an OLTP table but wanting to speed up a tiny subset of queries)

Closest thing I could find was Swarm64 for columnar indexes but it doesn't seem to be available anymore.