@lambda above has mentioned plugins.
As a matter of fact, I had started exploring this idea a couple of days ago, because I find it a bit annoying and wasteful that I have to distribute a whole executable binary just to let people try out a new module.
It is actually fairly simple to implement a plugin system for darktable. We just need to extend the module api with a way to specify a module’s position in the pipeline. For example, each module can declare after which “official” module it should go.
So, this is a viable option, which would take the burden away from the core dev team.
If there is interest, I can explore this in more detail.