Here's a 424-line strict-serializable, distributed, transactional key-value store, including a lazy, immutable hash-tree stored in an eventually-consistent datastore (e.g. Cassandra) and a single root pointer stored in a linearizable kv store (e.g. etcd). Exercised by Maelstrom/Jepsen, checked by Elle for transactional anomalies. Performance plots, concurrency traces, and Lamport diagrams help you understand system behavior.
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