citus VS rqlite

I see they don't mention Citus (https://github.com/citusdata/citus), which is already a fairly mature native Postgres extension. From the details given in the article, in sounds like they just reimplemented it.

I wonder if they were unaware of it or disregarded it for a reason —I currently am in a similar situation as the one described in the blog, trying to shard a massive Postgres DB.

It is possible, if you pay for it. You can do Multi-AZ Clustered Instances in RDS, where you get the benefits of Multi-AZ failover with traffic sharing.

If you can run your own infra – at least on an EC2 level – you can do things like Citus [0] for Postgres, which is about as close to "just add database nodes" as you'll get.

[0]: https://www.citusdata.com/

So while searching for something like this for postgres I came across citus. Any one know how that stacks up?

https://github.com/citusdata/citus

References: CitusDB

Seems like you could do the same with rqlite [1], since SQLite supports JSON.

[1]: https://rqlite.io

rqlite[1] creator here, happy to answer any questions about rqlite, this latest release, and how it works.

[1] https://rqlite.io

I found simple distributed RQlite https://github.com/rqlite/rqlite based on raft and sqlite. How hard is to add it?

rqlite[1] creator here, happy to answer any questions. rqlite also supports read-only nodes, which can also help with reads at the "edge". It probably wouldn't scale to 100s of nodes, it is an option.

"rqlite supports adding read-only nodes. You can use this feature to add read scalability to the cluster if you need a high volume of reads, or want to distribute copies of the data nearer to clients – but don’t want those nodes counted towards the quorum. These types of nodes are also known as non-voting nodes."

[1] https://rqlite.io/

[2] https://rqlite.io/docs/clustering/read-only-nodes/