About performance of FoundationDB:
https://foundationdb.com/key-value-store/performance

Application Integration:
https://foundationdb.com/layers/sql/documentation/AppIntegration/index.html

PostgreSQL drivers compatibility

The SQL Layer “speaks” the PostgreSQL protocol. Therefore, any PostgreSQL client driver can be used to connect to any SQL Layer instance. Almost every language has such a driver and a complete list is maintained at the Software Catalogue - Drivers and interfaces section of the PostgreSQL documentation.

One important difference is that the SQL Layer exposes standard metadata tables <information-schema-index> whereas Postgres has pg_xxx System Catalogs tables, and as a result some drivers relying on metadata queries will log errors on startup. If you’re trying to use or fork a driver or ORM not listed here, check out the troubleshooting untested drivers and ORMs section below.

I have begun to try to transit to FoundationDB,
cause it uses Postgres protocol, I have made some changes to Zabbix Frontend and it works, sure with mistakes, but all reads work and users update.

I know you work about mid-layer between Zabbix and NoSQL databases what about to add FoundationDB.