2026-09-02 | What I Learned About User Interviews
Software developers are very good at building things. Unfortunately, this is only useful after they have picked the right thing to build. A few years ago, I co-owned a startup that developed software for relationship management. It was similar to a CRM, but focused on building a professional network rather than managing a sales pipeline. We had plenty of ideas. We also had the technical skills to implement them. What we did not have was a reliable method for deciding which ideas deserved to be implemented. It took us more than a year and several expensive wrong turns to understand some fairly fundamental facts about our product: it would be used for business rather than private relationships, it needed both a mobile and a desktop version from the start, and the right customers could justify paying around 100 Euros per month. In hindsight, none of these insights required a year of software development. They required better conversations.
2026-08-09 | A REVERSI engine from high school
My REVERSI move engine, originally written in Pascal in 1992 and now ported to ClojureScript with a modern UI
2026-07-22 | Unorthodox Solutions for Fizzbuzz
This post discusses several approaches to the Fizzbuzz group word game. Starting with the standard approach, I introduce a couple of restrictions that require more creative and unorthodox solutions.
2025-09-02 | My Colleague With the Super Power!
I once had a colleague with a super power. No, he couldn’t fly like Superman, manipulate minds like Professor Xavier or heal like Wolverine. He had a really useful super power: He could read Python regular expressions! For mere mortals regular expressions are write-only collections of control characters and they have a very hard time understanding, let alone analyzing or debugging them. For those of us who don’t have a super hero ready to rescue us damsels in distress, we can use commented regular expressions, as in
2025-07-01 | Why Would Anyone Use COBOL Today?
According to the “Mythical Man-Month” a programmer is more productive in a concise, expressive, and powerful programming language and COBOL is quite the opposite. It is clumsy and verbose. At least, that’s what most people think. I have written two books on iOS programming, one about Objective-C and the next one about Swift. A while ago, my publishing house called me and asked me whether I wanted unsold copies of my books for free. They couldn’t sell them anymore. Why?