Maven, Microservices

Maven Archetypes

We found a structure that works for our service.(eg clean architecture). That means we have a domain layer, a data access and application layer and of course our presentation layer which can be a rest endpoints layer. Now we want all our services to respect this structure and also we don't want to manually copy… Continue reading Maven Archetypes


Sagas in microservices

We all know that the shared data in microservices(if they are done right) is eventually consistent. This is due to the CAP theorem which states that availability is usually a better choice than consistency. In a previous post I wrote about having eventual consistency data using Eventuate. Since distributed transactions(2PC) are heavy with a bad… Continue reading Sagas in microservices


Microservice versioning

Why do we need to version our microservices? Microservices are basically APIs. These are consumed by the clients. We should be able to evolve them without any impact to the clients. We should not force the clients to use the new changes in services and more importantly this should not break the clients. There must… Continue reading Microservice versioning


Securing microservices

Microservices are hard. Complexity is high. Securing microservices is even harder and even more complex. Where do we start? The first words that come to my mind are authentication and authorization. Firewall. Trust. Session. Tokens. We need to secure our applications and we need to secure our containers. Securing applications We can build a SSO… Continue reading Securing microservices


Log tracing with Sleuth and Zipkin

In a microservice environment it's hard to trace errors and logs, as we have lots of moving components. We could go into each service and read the logs, then aggregate them and finally with lots of patience try to understand what is happening. But we should not do this, we have alternatives. One of them… Continue reading Log tracing with Sleuth and Zipkin



Microservices should respect the CAP theorem. That means when a failure occurs, you should choose between consistency and availability, and availability is the best choice. Hystrix has the role to keep the availability high when a partition occurs, by stopping cascading failures and providing fallback. These partitions should not be visible to the end user,… Continue reading Hystrix


Eureka and Feign

Eureka Eureka is a REST (Representational State Transfer) based service used for locating services for the purpose of load balancing and failover of middle-tier servers. We have eureka client and server. The server holds the information regarding the service instances, while the client interacts with the server and act as a round robin load balancer.… Continue reading Eureka and Feign