I originally created Website Launch Checklist as a bit of an experiment to find out if owning an domain name which exactly matches a given search term is of any particular benefit to SEO (turns out not really).
The content is clearly nothing revolutionary, but since the fairly simple original version I've redesigned the site a couple of times when I've been learning a new technology or just wanted something to fiddle with. Its current guise was created when I needed to refamiliarise myself with Redux, so it's built in Next.js with Redux/Redux Toolkit and Redux Persist handling all of the state management.