I have a related anecdote but no advice for your goal of 1-2 days promo then leave it. Once upon a time I also made some software for a similarly real but nich

I have a related anecdote but no advice for your goal of 1-2 days promo then leave it. Once upon a time I also made some software for a similarly real but niche problem (recording, processing, and building timelapse videos of your work during hackathons). I never promoted it or anything beyond talking about it and using it within the community where the idea was born (in my case, ludumdare when it was still very small). It has actually done pretty well within that context; over the 8 years or so it has been around it has ~50k installs, and it has branched far beyond hackathons -- it made its way onto lifehacker when they still covered real products, there are a handful of completely independent reviews out there, and I get emails from time to time asking for features from a wide range of use cases (everything from documenting cell growth to filming engine rebuilds to tracking video game progress in a modernized arcade). My only (admittedly weak) advice is to go to the source of how you knew this was a need and share it openly and honestly within a community that is either about that or clearly shares that. From there you'll get some feedback and, if it really does solve a pain point, people will use it and share it. In my story, the flexibility of the product to be useful beyond the initial problem I was trying to solve was also key to its growth - maybe you can do something similar with how your thing works. I realize that 8 years of being available is the complete opposite of your goal of promoting for only '1-2 days', but I think that amount of participation may not be super compatible with any software these days, particularly for small 'love' projects. How many github projects have you seen that sound nifty but have an empty readme and no commits for 2 years so you wouldn't touch it with a 10 ft pole? I think you'll get much better results by trickling continued time into the product to make sure people know it is alive - respond to posts/questions about it, fix bugs (or at LEAST comment on the issues), etc.