Hibari is a distributed, fault tolerant, highly available key-value store written in Erlang. Data replicas are managed by chain replication rather than the more common quorum voting technique used by Riak, Cassandra, and others. Hibari supports micro-transactions (atomic updates to multiple keys in limited circumstances) and cluster resizing (both growing and shrinking the cluster). Hibari clients can be written in Erlang as well as C, C++, Java, Python via the UBF protocol and soon in other languages via Protocol Buffers and Thrift. Hibari was released to the open source community under an Apache License v.2.0 and is available at http://hibari.sourcef.... Hibari's largest commercial deployment is a Webmail system in Asia that is managing approximately one billion email messages. My talk in Chicago will be the Hibari's first public presentation. I'll talk about its major features, how chain replication works, and how Hibari's sponsor (Gemini Mobile Technologies) will manage code patches from the open source world. I'll leave the rest to audience questions, with just-in-case material for demo'ing things like cluster expansion/contraction and developing a small client application that uses micro-transactions.