This is deliciously ironic for me. For those who aren't aware, Armin is the original author of Flask, the Python web framework. Around the same time, there was a very similar library called Bottle. They were almkst identical in functionality, but while Flask became very popular, I always preferred to stick with Bottle because it was a single file with no dependencies, which meant it was very easy to just copy into your project.

It also made it very easy to hack around with, and I got to the point where I understood the entire thing. I did couple it with Gevent for the server and websockets, but I was able to put together some heavy-lifting projects that way.

I still feel a strong impulse to use it for small web projects. Sadly, it didn't keep up with a lot of the more modern practices that Python has introduced over the years, so it does feel a bit dated now.

Seems like a better comparison would be any schemaless binary format, like msgpack, bson, or the many others. This adds some basic type validation, which you would have to do with a separate library, like msgspec if you're using Python.