Opensource alternatives to Postsharp

Question

Someone knows a good alternative Opensource at the Postsharp? I know it has the Free version, but I am developing some Nuget packages using attributes and I find the dependency of Postsharp heavy and at any time they can start charging, depends on license.. I even have an annoying problem with it the license Appveyor here.

I need to specifically work with Custom attributes as we do in Postsharp, yesterday I found one and started testing: https://github.com/AntyaDev/KingAOP , but did not meet me 100% and the project is 5 years without change.

Suggestions are welcome.