I believe seastar uses it and that is the base of scylladb storage engine: https://seastar.io/

I believe the next generation ceph OSD is built on seastar as well: https://docs.ceph.com/en/reef/dev/crimson/crimson/

With something like ceph, latency is everything as writes need to be synchronously committed to each OSD replica before the writing client is unblocked. I think for ceph they are trying to move to nvme-of to basically bypass the OS for remote NVME access. Im not sure how this will work security wise however as you cannot just have any node on the network reading and writing random blocks of nvme-of devices.

> I believe seastar uses it and that is the base of scylladb storage engine: https://seastar.io/

They use DPDK (optionally) for network IO, not SPDK.