To author native Universal Windows Platform (UWP) plug-ins, you need to know how to create native plug-ins for Unity. For more information about native plug-ins and their uses, refer to Native plug-ins.
To author native UWP plug-ins, you can use either a precompiled dynamic-link library (DLL) or the C++ source code.
To P/Invoke into precompiled native plug-ins, you need to:
You need to compile the DLLs against the appropriate Windows SDK for the target CPU architecture. You also need to configure the DLLs in the Plug-in Inspector when you add them to a Unity project.
You can add C++ (.cpp) code files directly into a Unity project, which will act as a plug-in in the Plug-in Inspector. If you configure the plug-ins to be compatible with UWP and the IL2CPP scripting backend, Unity compiles these C++ files together with the C++ code that it generates from managed assemblies.