Software that works.
In production.

Migrating from Spark to Javalin: You Can't Strangle a Web Framework

Changing a web framework must be done the same way you would change an aircraft engine midair. You do it prudently, in small, safe steps all the way. You test everything so no surprise surface when you do the switch.

I moved LogEze to Javalin. It is a product I have built since 2014, and it ran on the Spark Java web framework until recently. The cutover was one environment variable. I flipped it and everything switched from Spark to Javalin at once. Most of the work was in the preparations. Two weeks of them were hands-on work, abstracting Spark away from the core of the app far enough that a parallel Javalin implementation could be built alongside it and switched on safely. The rest started a lot earlier, with spikes to settle on the replacement and a shared super class that every controller already ran through, in place more than two years before I needed it.

A Revival for Test First, If We Don't Waste It

Using a coding assistant might turn out to be the best thing that has happened to Test-Driven Development (TDD) so far. This is the seventh post in my series about coding with an assistant.

For more than twenty years the objection to TDD was always some version of the same thing. No time. Too much typing. We will add the tests later. The assistant removes that objection. It types the test for you in seconds and it does not get bored doing it. On top of that, the path of least resistance with an assistant now runs straight through the test. I made that case in Fitness Functions for an AI Coding Assistant. To get useful work out of the assistant you have to tell it what done looks like, and a description of done that a machine can check is a test. TDD stops being the disciplined choice and becomes the efficient one.

Fitness Functions for an AI Coding Assistant

This is the sixth post in my series about working with an AI coding assistant. The earlier posts covered getting started, observations, rules, results, and communication. This one is about the gap between a rule the assistant might follow and a constraint it cannot get around.