Blog

Commit early, commit often, even when the tests are failing

How to commit code to version control systems… I suspect that there are at least as many approaches as there are people making software. Nevertheless, it is a topic worth to explore, and to challenge. Don’t expect an article that is exclusively talking about version control though, if anything this is a story on teamwork.

Decisions should not be boring to read

Have you ever looked at a domain model or an implementation of it and wondered: Really?! What were they thinking 🙄

I certainly have found myself in such a position in the past. Often it turned out that I had been the person who had taken things into a particular direction. However, the details of the decisions I had made in the past – which resulted in the current domain model – were no longer present in the forefront of my mind. 

A Different Take on Context Mapping at DDDEurope 2020

Watch me explore how we can improve mapping in DDD at DDDEurope 2020. Can we make space more meaningful in a typical Context Map? How can we visualize our intended changes? Is there a way to markup maps with forces on our model outside of code? And what impact can we expect from things not part of our map?

Immutable projections

The first time I took an Event Sourced domain model to production it was tough. In part because I applied CQRS and Event Sourcing as a top level architecture. You probably shouldn’t do that. Unless you know what you’re doing and no supporting subdomains are in scope.

But we were young and foolish. So by the time our understanding of the domain had grown, we had to modify a whole bunch of models that were in production. This isn’t a bad thing but it can be a tough job if you haven’t done it before. Because how do you change a projection without causing problems or downtime for your customers? And how do you know it works as intended? Back then we tested a lot on a staging environment, we timed well and we crossed our fingers #startuplifeyolo.

But please, save your hair and don’t use that approach. Use feature toggles instead to evolve your models with ease.

The best moment is now

As a professional trainer I get to deal with a lot of interesting dynamics when it comes to education and practice in organizations. By far the weirdest behavior is the urge to postpone a training if someone cannot join.

Experimenting with Event Sourcing and CQRS where it matters

A few months ago I upset some people with some tweets about CQRS, Event Sourcing and my views on applying those techniques in certain domains:

The lost art of bookmarklets

Bookmarklets, I think they are an underrated tool in the toolchain of problem solvers today. They can be fast, contextual, visual and cheap to build. What is not to love?

How I use Live Templates in PHPStorm

How fast you can type is usually not a constraint on software design work. However, having to write the same boilerplate code again, and again, and again can be quite a drag. Over the years I’ve started to use PHPStorm – my IDE of choice – better and better. One of its features is “Live Templates”. These can be used to generate small sections of code in particular types of contexts, like files, class bodies, method or function bodies.

Write to be understood

Communication is difficult and that is why misunderstandings happen. Some people feel that they have “communicated it” when they have “told someone”. In my opinion that is too easy. Making sure someone understands your point of view is for a large part the responsibility of the person sending a message. And that responsibility includes seeking confirmation if what was communicated is also understood.

Start somewhere or steal something

There you are, at the beginning of a remarkable mission, that you decided to embark on. The goal is clear, you can see most of the steps that you are required to take, but still it seems daunting.

A list of random tips for Event Storming facilitators

Learning to facilitate an Event Storming workshop requires trial & error. Effective and useful Event Storming workshops have a mix of people with questions and answers. As such aspiring facilitators need to learn facilitation with a mixed group of participants, most of whom might not be so patient with the learning cycle of the facilitator to be. This list of training wheels will help you get started and prevents common pitfalls.

What Would Marijn Do Cheat Sheet

When I said goodbye to a corporate client last year, I decided to leave the team a cheat sheet in case they got stuck. It was a joke and like many jokes I make it was probably poorly understood.

Strategies for Dealing with Environment Variables

How often have you found yourself sifting through a configuration file to look up some settings? That can be quite a daunting task on some projects, right? I just picked three large projects I worked on. They contained 38, 121 and 68 parameters respectively.

Naming pattern for Exceptions

Sure, you’ve heard it before: naming is hard. I’m also confident that this isn’t the first time that someone tells you to drop technical patterns from your naming strategies. But have you ever tried it? And if you did; have you applied yourself to take it beyond the obvious?