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SMEs, Steer Clear of Microservices!

April 15, 2024

Latest Posts

Softwareentwicklung im Mittelstand June 22, 2023

El Niño

Hi, El Niño is back. The surface temperature of the Pacific Ocean periodically fluctuates. This seemingly inconspicuous change triggers a cascade of weather changes that extend their influence to the most remote corners of the globe. Floods in South America, droughts in Australia, and even snowstorms in North America - all caused by a few degrees of temperature difference in the Pacific. This phenomenon occurs every 2 to 7 years. This year, it’s that time again.

Marcus Held

Software-Architektur July 28, 2022

Microservices are a Big Ball of Mud

Over the past years I attended hundreds of interviews. Many candidates proudly told tales on how they develop their projects with a microservice architecture. Often (I don’t want to say “always”, but from my memory I think it actually is “always”) it does not require many questions to see that they used a rocket launcher to kill a mouse. Microservices are hard. Everyone who experienced the pain of operating such an architecture can relate to it. The complexity kills you at one point or the other. You already had to do multiple refactorings of your architecture - because your domains didn’t work out. I wonder - why is this architecture so appealing to developers? And then I remember why I found them appealing 10 years ago.

Marcus Held

Entwicklungspraxis March 20, 2022

Java Bean Validation is an Anti-Pattern

The javax.validation package is widely used in our industry. And I don’t like it. I believe using bean validation is an anti-pattern. It hides business relevant constraints, it leaves the choice when a validation happens to other framework code, and I even saw cases where developers expected that the validation “just had to take place”, but it never happened. Of course, there was also no test for it. And speaking about tests - testing these business relevant constraints is painful as well.

Marcus Held

Entwicklungspraxis August 2, 2021

Prefer UUID for your Primary Key

In my last post I discussed the downsides of using numerical types for the primary key of an entity. We should avoid these issues all together by using UUID instead and in this post I will discuss the up- and downsides of this approach. Using a UUID as the primary ID is simple: @Entity class Flat( @Id val id: UUID = UUID.randomUUID() ) Generate the ID on the application Similar to numerical ids we can generate it on the database as well. But for UUID this is not necessary. The reason we did this in the first place is that we needed to make sure that an ID is not used twice. A collision of UUID is very unlikely to occur.

Marcus Held

Entwicklungspraxis July 15, 2021

The Inevitable Consequence of a Numerical Id

In many (JPA) applications numerical ids are chosen for the surrogate key of the entities. But how do we make sure that they are not used twice? In a scenario where our application needs to scale horizontally we need a solution for that. Most developers come to the conclusion that the database should take care of that. But this is a fragile solution and in this article I want to discuss it.

Marcus Held