Zookeeper-clj is a Clojure DSL for Apache ZooKeeper, which "is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services."

Out of the box ZooKeeper provides name service, configuration, and group membership. From these core services, higher-level distributed concurrency abstractions can be built, including distributed locks, distributed queues, barriers, leader-election, and transaction services as described in ZooKeeper Recipes and Solutions and the paper "ZooKeeper: Wait-free coordination for Internet-scale systems".