Modern Complex Event Processing (CEP) systems often need an high degree of customization in order to implement required application logic. The use of declarative languages, such as CQL, often leads to complicated and hard to maintain application code. In this demo, we show how state machine-based CEP operators help to cope with these problems. State machine-based CEP operators allow for a high flexibility as well as a re-usability of application logic components. A major benefit of the presented solution is its easy integration with existing streaming engines, which we demonstrate using StreamMine, a highly parallel and faulttolerant streaming engine prototype. In this demo we show: (1) how state machine-based operators allow for an easy definition of custom, reusable CEP operators, (2) how resulting state machines can be easily combined with existing faulttolerance techniques within StreamMine and (3) how the resulting CEP applications can be tested in a cost efficient way.