irmin-fdb implements an Irmin store backed by FoundationDB. The implementation is based on ocaml-fdb.
See the Irmin tutorial for more information onwriting storage backends for Irmin.
Installing libfdb (download here) is a requirement for using irmin-fdb.
This package is not available on OPAM yet, but in the meantime you can install it in the following manner:
opam pin add irmin-fdb git://github.com/andreas/irmin-fdb.git
dune build
dune runtest