One way you can do that is by architecting something like chmod. Basically a point based system. 7 gives all, 1 gives read. You can then have your actual implem

One way you can do that is by architecting something like chmod. Basically a point based system. 7 gives all, 1 gives read. You can then have your actual implementation compiled away, but can change points for a user as and when you like. The code that checks won't need to be recompiled.