RacquetRivals.com
My wife and I used to create brackets by hand for the last 16 players of the four major tennis tournaments. We had so much fun I made it into a web app, like March Madness. Sign up, add your predictions during a major tournament, and you'll be awarded points by round for correct choices. You can compare scores with your friends along the way. The frontend is built with SvelteKit hosted on Netlify, and the backend is Pocketbase hosted on a Digital Ocean Linux Droplet.