The Riak key-value database: I like it
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(Note: This is a writeup I did a few years ago when evaluating Riak KV as a possible data store for a high-traffic CMS. At the time, the product was called simply “Riak”. Naturally, other details may be out of date as well.)
Riak is a distributed, key/value store written in Erlang. It is open source but supported by a commercial company, Basho.
Its design is based on an Amazon creation called Dynamo, which is described in a 200-page paper published by Amazon. The engineers at Basho used this paper to guide the design of Riak.