I'm working on a project right now that is essentially a set of libraries for game development. The idea is that these modules (in the form of DLLs, jars or other extensions) are open source and can be exchanged with custom ones the user builds. Developers can mix and match which modules they need and build connections to them in a closed-source manner.
It used to be BSD-3 because originally it was just code that could potentially be copied, but I feel like shifting the design into a bunch of modules makes a GPL-like license more attractive (and just easier for people to use). Since they are modules, only the custom module would be restricted under the license, not the entire codebase.
I want to make sure that the modules are still attractive to developers though - so I want to make it so that the modules cannot be hardcoded into these engines themselves, but can still be freely. The purpose of these being modules is to be switched out and it defeats the purpose of this ability.
Would this count as "free use" of the module? In my head it seems right but I don't want to jump the gun and intimidate devs down the line.
Are there good examples of licenses that I can reference as well that have a similar problem? Sorry if this sounds dumb I'm just intimidated by the length of everything.