[DmitryOlshansky]

I recall the Zookeeper paper from Yahoo scientist which basically details a more useful version of Google’s chubby. I find reliability and design of Zookeeper fascinating these days cool kids use etcd mostly because of relatively complex protocol of Zookeeper (there is a few implementations but they lack the polish of Java client).

[zX41ZdbW]

There is a drop-in, protocol-compatible replacement for ZooKeeper - ClickHouse Keeper: https://clickhouse.com/clickhouse/keeper

Many applications depend on ZooKeeper's data model and client libraries, and can't switch to etcd. Things like watches and ephemeral nodes are different there.

[gethly]

iirc problem of the zookeeper was that it was a chunky java application. etcd is tiny go binary. so there is more to it than just complexity of the protocol itself.