What is a good size for a microservice?
To be able to answer that we should start from a different question: what kind of problems we believe smaller/independently deployable codebases solve better than a monolithic codebase with a single deployment unit? I think there are two main problems microservices can help solving: runtime scaling iteration speed Depending …
Read moreBuilding modular apps using Spring
When looking at most of the sample applications and code examples for Spring framework it may seem that everything should be defined as a bean. However, if we want to achieve nicely modular design then we should try to do the exact opposite - have each module expose as little …
Read moreHibernate and Domain Model Design
When I first learned about Hibernate about 12 years ago (I guess just about when it was at its peak) I found it to be one of the coolest libraries ever created. Hibernate made it possible to use OOD in practice! Build complex domain model graphs that were not only …
Read moreIllusion of Reuse
I have quite often seen situation where trying to achieve more reuse actually ends up in building the Big Ball of Mud. In some cases it is the Enterprise Domain Model that Eric Evans warns us against. Other places which are especially susceptible to this are Transaction Scripts and other …
Read more5 Tips for Getting More Out of Your Unit Tests
State of Application Design In vast majority of applications I have seen the domain logic is implemented using a set of Service classes (Transaction Scripts). Majority of these are based on the DB structure. Entities are typically quite thin DTOs that have little or no logic. The main benefit of …
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