I built Anime-dle as a little side project in July 2022 towards the end of Covid and the Wordle / Framed boom. The initial version took a couple of evenings, since then it's had a continuous stream of improvements.
It's always had a consistent user base despite the lack of promotion of it, and me ocassionally neglecting it for a few months here and there. And amazingly users play around 4k puzzles a day.
The "magic" that makes it work is this little side project I did to scrape images from Reddit Anime discussion threads. If you're interested how I did it it's documented in detail here.
This let's me create puzzles relatively quickly, and is how it's kept going for over 3 years now.
It's been re-platformed and re-developed several times and has been amazing for building my web dev and hosting skills.
The core of it has always been a static site built with Bulma for our look and feel, and jQuery for the interactivity. Initially I used Azure Application Insights for recording all of the metrics about win/losses, but since I've moved things to a far more sensible Python Flask API backed onto MySQL.
It's now hosted on Kubernetes on a modest Hetzner node, so it runs for around £4.86 a month.