Elegant delegates in Kotlin
Kotlin has given us some really killer features. Some are obviously useful, while others come with a warning. One such ‘handle-with-care’ feature is the language support for delegation. Read more
Posts by Jasper Sprengers
Anti-patterns part 2: Coding is the biggest Golden Hammer of all
Today I want to talk about what is perhaps the most infamous of all: the Golden Hammer. Actually, it’s a collection of hammers that makes up the toolbox from hell. Read more
When anti-patterns become a pattern
There are plenty of learning resources on software best practices. Sprinkled in between all the well-intended advice are warnings about... Read more
The most useless knowledge of all
There are things a programmer needs to know, no excuses. There are things you can’t possibly all remember, so it’s... Read more
Not everything that is vital is also your core business
Large software projects have many vital concerns, such as authentication and authorization. Despite the wealth of available libraries in the... Read more
In defence of pedantic tools
We aim to please the customer at short notice and always overestimate our capacity to comprehend a system as it gets more complex. That’s a recipe for technical debt. Read more
Mocks or the real thing? Tips for better unit testing
This is not a tutorial about how to exploit the advanced features in modern mocking frameworks. Rather, it’s a warning that these features work around design decisions that were wrong to begin with. Read more
Essentialism for developers
Essentialism – the Disciplined Pursuit of Less by Greg McKeown is a book with an essential message: much of life... Read more
The vicious circle of bad test code and how to break it
SUMMARY Compared to the great advances in programming languages and tools, the day-to-day practice of how we actually code is... Read more
CRUD operations on Spring REST resources with Kotlin
In this practical, hands-on post I would like to share some of my experience in building REST services wih JSON... Read more
Integration testing strategies for Spring Boot microservices part 2
This is the second part of my earlier post about strategies for integration-testing Spring Boot applications that consist of multiple... Read more
Integration testing strategies for Spring Boot microservices
SUMMARY: Unit tests are a necessary condition to clean code, but today’s convention-over-configuration frameworks like Spring Boot are often used... Read more
Web frameworks and how to survive them
SUMMARY: Frameworks that help build the web apps of tomorrow must keep up with all powerful new technology there is... Read more
Kotlin’s killer features
SUMMARY: Kotlin is a new JVM language fully interoperable with Java bytecode. It is clearly inspired by Scala, but has... Read more
Caching de luxe with Spring and Guava
Summary We generally don’t optimize expensive operations in code until they create a bottleneck. In some of these cases you... Read more
Sensible mutation testing: don’t go on a killing spree
This is a follow-up to my earlier post about mutation testing (MT). To recap: MT helps you ensure that your... Read more
Mutation Testing: Watching the Watchmen
You can’t do without automated (unit) tests if you want to stay on top of the ever increasing complexity of... Read more