Processing event streams is an increasingly important area for modern businesses aiming to detect and efficiently react in near real-time to critical situations. The need to govern the behaviour of systems where such streams exist has led to the development of numerous Complex Event Processing (CEP) engines that are capable of detecting patterns and analyzing event streams. Although current CEP systems provide real-time analysis foundations for a variety of applications, several crucial challenges arise due to languages’ limitations and imprecise semantics, as well as the lack of power to handle big data requirements, but moreover the lack of scalability of existing CEP. In this talk, we present LEAD our fully distributed CEP based on a formal algebra to tackle the semantics issues and that leverage the stateful nature of Apache Flink to get a fully distributed CEP. We want to call for contributors who can make this prototype a first-class Flink CEP.