• I wouldn't write a test for that

    Last week, I was helping a colleague who was working on a small application. One component was responsible for sending data to a configured recipient. I suggested writing a test to verify that an email was actually sent containing the relevant data in the body. This led to the following discussion: continue reading
  • Advent of Haskell, Part 2

    It’s already been more than two weeks since I started my little Advent of Code + Haskell adventure. So it’s time for a little update. Here’s what I got done. Day 2 Puzzle description Regular expressions are often my first choice when I have to parse something. Like in this case, to get the values easily out of strings like 6-8 b: bbbnvbbb. continue reading
  • Approaching 100% code coverage in a healthy way

    One question the always comes to my mind in the discussion about code coverage is: What does the percentage refer to, anyway? This is probably a stupid question. It seems to be common sense that it is the whole codebase. But does it really have to be? What is the value of code coverage, again? continue reading
  • Advent of Haskell, Part 1

    This year is the first time that I participate in the Advent of Code. What I learned right on the first day was that some people would finish the whole puzzle while I was still sipping on my morning coffee reading the assignment. I like challenges but I don’t know whether I can compete with what’s going on in the leaderboard. continue reading
  • About confidence, code, and tests

    Whether you’re reading a classic like “Test-driven Development by Example” by Kent Beck or a yet another article on medium. When it’s about testing, there’s always some talk about confidence. That made me think. Can you be confident about your code when you don’t have tests? The question seems ridiculous. continue reading