Couldn't this still work as a service if you run all queries through the front-end?
Also, it's just a proxy, there's no front-end. (Being a 50 line Python script with one dependency (Flask), the idea is that the end user would run it.) It's just http://localhost/URL, and it loads it from the hardcoded snapshot. I guess https://localhost/snapshot/url might work better.
I'd also like to see how many lines it ends up being if you remove the one dependency. I've done this for other projects and the answer is "not much more" and "also runs way faster for some reason."