  Microservices architecture has been widely adopted to develop software
systems, but some of its trade-offs are often ignored. In particular, the
introduction of eventual consistency has a huge impact on the complexity of the
application business logic design. Recent proposals to use transactional causal
consistency in serverless computing seems promising, because it reduces the
number of possible concurrent execution anomalies that can occur due to the
lack of isolation. We propose an extension of the aggregate concept, the basic
building block of microservices design, that is transactional causal consistent
compliant. A simulator for the enriched aggregates is developed to allow the
experimentation of this approach with a business logic rich system. The
experiment results shown a reduction of the implementation complexity. The
simulator is a publicly available reusable artifact that can be used in other
experiments.
