Roadmap: Any plans to support other metadata backends?

Currently, 3FS only supports FoundationDB as the metadata backend. I understand that FDB is a distributed transactional key-value store that perfectly fits 3FS's needs. However, its popularity is somewhat limited, and many companies may lack the operational experience and tools to manage it effectively.

For example, [JuiceFS](https://juicefs.com/docs/community/databases_for_metadata/) supports not only FDB, but also Redis (including Redis Cluster), TiKV, and relational databases like MySQL and Postgres.

Is there any plan in the community to move in this direction?

P.S. We're particularly interested in relational databases and would be open to contributing if possible.