Cloudflare used to use Kyoto Cabinet[1] and moved to LMDB[1] in 2020; other implementations that I'm familiar with (but don't have a link to share) also use LMDB.
> Are people still using DBM-style storage generally?
It's fairly common in these scenarios, as well as the underlying key-value store for popular software like Consul[3].
[1] https://blog.cloudflare.com/kyoto-tycoon-secure-replication/
[2] https://blog.cloudflare.com/introducing-quicksilver-configur...
