I made a public transport route planning program that's capable of planning journeys across Europe or North America! There's only one other FOSS project I know of (MOTIS/Transitous) that can do transit routing at this scale, and in the testing I've performed mine is about 50x faster. I've spent a few weeks on this project now and it's getting to the point where I can show it off, but the API responses need a lot of work before they're usable for any downstream application.
Example query (Berlin to Barcelona): https://farebox.airmail.rs/plan/52.5176122,13.4180261/41.380...
There are some bugs still. Notably, it's not capable of planning the return trip for this route, nor the reverse of the trip from Seattle to NYC that I gave in the blog post.
Blog post: https://blog.ellenhp.me/performant-intracontinental-transit-...
Repo: https://github.com/ellenhp/farebox
Side-note but in the past some have criticized my writing style and it's been a bit hurtful at times but if you have constructive feedback on the blog post I'd appreciate it. I'm trying to get better at writing. :)