Thank you for your response! I had sort of arrived at the same conclusion. In our current state Casbin would arguably be the easiest and fastest to implement and would work fine for a long time. However, as the company grows it is indeed likely that things are broken up into different services or new functionality is added as a service. As the amount of users increase it makes even more sense to separate this into a different service. All that remains is the easy task of convincing my colleagues who live in the "grow fast and just do" mentality.