The newly added feature of Coprocessors within HBase allows the application designer to move functionality closer to where the data resides. While this sounds like Stored Procedures as known in the RDBMS realm, they have a different set of properties. The distributed nature of HBase adds to the complexity of their implementation, but the client side API allows for an easy, transparent access to their functionality across many servers. This session explains the concepts behind coprocessors and uses examples to show how they can be used to implement data side extensions to the application code.