Filthy Casual
I speedrun a game. So of course I made a tool for it.
I got into speedrunning Super Metroid many years ago.
You quickly find if you're speedrunning a game that the best tool for the job is a stopwatch. This is especially true if you are the type of person who can't always find enough time to do a full run in one sitting.
There are excellent speedrunning tools out there already, but at the time I started running virtually none of them had what I needed: the ability to pause the run and come back days later and resume it.
So I built a little tool to do that and used it for 100 or so runs.
With some help from ye olde LLMs to improve the actual look of the site, I have started using this version of it.
It's rough and is only a very small step above an internal toy you'd never show anyone, but I think it's at the point it might be useful to someone.