Hey guys, I want to use this library in my game, which allows me to generate QR codes at runtime, and with some tinkering I could create a texture2d out of them and make a handy blueprint node. Problem: i don’t know how to use those external libraries inside UE. Do I need to add all .c/.h files inside my project’s source folder? How does UBT compile them? Oh, and as I said, they are C files, not C++… Do I need to do some extra work to get this working? Thanks for help 
Hi,
It can be done relatively easy. You need to define, whether you will build your library separately or you will directly include all library files. If the first, build your library to use it statically/dynamically and follow the following documentation: Third-Party Libraries | Unreal Engine Documentation
If the second, just include all files directly. You don’t need to do any kind of extra work, if your library doesn’t contains any external dependencies and can correctly work with namespaces.