Riak is the Swiss army knife of unstructured data storage. Initially built as a key-value data store, very similar to Amazon DynamoDB, Riak has since evolved and now integrates highly advanced functions that have allowed it to stand out from the competition:
The solution's main strengths lie in its ability to integrate third party languages and its easy-to-administrate cluster. Its vendor support is a definite plus. It should be noted that the solution also has a hook mechanism that can be used to introduce complex functional logic into the storage layer or for integration with third party environments. These validators can be written in Erlang (the language used by Riak's core) or in JavaScript (via the Rhino engine). This makes it one of the most scalable solutions in this segment. It is true that Riak's performance is not the best in our selection of NoSQL solutions, but its performance levels remain very high all the same. In our opinion, this is an acceptable trade-off in most cases, taking into account the high level of functionalities provided by the solution.