Have a look at https://gdal.org/index.html
Solved a lot of weird open formats issue we had
Thanks but I already wrote the code and after catching a couple gotchas with the validation tool it's fully compliant now.
My point was not that GPX is hard (it's not) but that when something is open source most of the time you have to put some elbow grease in it because no one is paid to make it polished.
FWIW, it took me less time to write the GPX export code than to look for a binary of the validation tool, fail, then launch WSL and compile the goddam tool.
What does your app do? That's an area I'm pretty interested in.
It's a desktop (Windows) map viewer.
I have built my own OSM server to pre-generate tiles so my app has offline capabilities (I have a very slow internet connection so online maps are quite laggy).
I use it mostly to build routes that I export as gpx files to my Android phone (vehicle nav with Osmand and trekking with Iphigénie).
this sounds super useful to me (I have been in similar situations in the past @ various formats that aren’t super popular).
Apart of a few well known projects, the open source world is not so rosy.
I'm building an app that exports GPX files (XML file where you can store GPS positions, POIs, routes etc).
All the examples files on the official website ( https://www.topografix.com/gpx.asp ) are broken (they return a blank page) and to validate that your file is compliant you have to compile a 15 years old C++ library first (for some reason they refuse to release a binary).