Zookeeper resilience at Pinterest

Curious to know what the daemon was written.. ie is this in python using kazoo (reimplementation of zkprotocol from scratch) or the buggy libzookeeper c client library.. or java (the only reliable official client sadly, and really for devs that often means netflix's wrapper around the java client).

zookeeper is nice.. and well known, battle tested, and a pita on devops (no dynamic reconfig till 3.5), and devs. a pain to interact with at reliable scale outside of native java clients, oh.. and the zk src.. cyclomatic complexity and npath complexity on large scales.

i keep hoping for something like etcd (raft + rest) can bring simplicity and ease of cross-language use for distributed coordination to the many.

This boggles the mind. Zk was so unreliable they threw out its fundamental guarantees and went to flat files mediated by a proxy daemon which talked to zk? What?