Citus is an extension to Postgres to make it a distributed, shared-nothing DBMS.
Citus Data was acquired by Microsoft in 2019.
Disk-oriented
Relational
Shared-Nothing
SQL
http://www.citusdata.com/
https://github.com/citusdata/citus
https://docs.citusdata.com/
Citus Data
TR , US
2010
Microsoft
Commercial, Open Source
PostgreSQL
AGPL v3