Hi, in a nutshell I have the following folder structure Code (CSharp): <root> ├── package.json ├── Scripts │ ├── SomeAssemblyDefinition.asmdef │ └── SomeBehavior.cs ├── Debug │ └── MyLib.dll └── Release └── MyLib.dll - 'MyLib.dll' is a managed dll - The define constraint 'DEBUG' was set for the version in the folder 'Debug' - The define constraint '!DEBUG' was set for the version in the folder 'Release' - 'MyLib.dll' was added to the 'Assembly Refernces' array in 'SomeAssemblyDefinition.asmdef' - 'SomeBehavior.cs' uses some code of 'MyLib.dll' Note that everthing is working perfectly when all these files are inside the asset folder in my project. But when I push them to git and load them as package in another unity project, I get compile errors in 'SomeBehavior.cs' that the namespaces of 'MyLib.dll' are missing. The problem seems related to the import of the dll. To my suprise I noticed, when browsing through the imported package in the unity project view, that the type of the dll was switched to 'native' and that the define constraints property was gone (I assume native dlls cannot have define constraints?). Is this a bug or a missing feature or am I missing something else? Or is there even a better way to switch between different dlls in a package using define constraints? Btw. I'm using Unity 2019.3.0b10 Thanks!