From what I can see this doesn't have built-in consumer balancing and offset storage, like Kafka does. It also lacks more exotic Kafka features like topic compa

From what I can see this doesn't have built-in consumer balancing and offset storage, like Kafka does. It also lacks more exotic Kafka features like topic compaction and exactly-once processing. In Kafka bulk reading is very cheap, the broker basically just calls sendfile() to send a file segment with compressed message chunks. On the other hand only the leader of a partition can serve requests, so you are often limited by bandwidth. It looks like LogDevice has to do a bit more work server side, but may be able to read from all servers with a replica. Kafka stores more metadata in the record wrapper, like client and server timestamps and partition key. There are client libraries for C++ and Python. Operationally they look similar - both require a Zookeeper cluster, and both require assigning permanent ids to nodes. It would be interesting to see some benchmarks comparing LogDevice with Kafka and Pulsar. That said, I suspect from the lack of buzz around Pulsar that Kafka isn't a performance bottleneck for most people using it.