This repository hosts the source code for dear-jour.nl website.
The website has an instructions page, which I think is pretty good.
Also, it's an ongoing exercise in building "an app for Zen meditation that must itself have Zen nature," so it was a conscious process of stripping down the feature scope until almost nothing was left. So, yep, there are a few hundred lines of HTML-CSS-JavaScript with no "AI" features, no covert data collection, no backend infrastructure at all, and, most of all, no plans to ever introduce any of that.
Of course, if you have some nice quirky questions you'd like to add to the list, you're very welcome to submit a PR!