Single Serving Software (Emom Timer)

I've been using a HIIT timer for workouts for years. It's gotten progressively worse - mostly due to ad creep. Long, loud, frequent, unskippable ads. I've stuck with it partly because of inertia and partly because every time I check the alternatives aren't a lot better.

Recently I've been on an EMOM (every minute on the minute) workout kick. The HIIT timer isn't purpose-built for EMOM timing, but I can make it work. Then I had the thought: "Why do I have to make it work?". With the modern crop of coding assistants, I can build an EMOM timer that works just for me in a few hours on the weekend. It's now my daily driver.