It's a question of responsibilities. Right now, it's used to determine which dll's to use on linux (on linux, see ffiModuleName), which means the distinction between 32/64 platforms is which ABI to use when doing UFFI, or more accurately, where to find libraries for the ABI supported by the vm. To make things less confusing, it would be better to remove the 32/64 subclasses from platform, (since they are really a separation only relevant to UFFI) and have the ffiModuleName: extension branch on Smalltalk vm is32/64 as appropriate for UnixPlatform. Then one would be free to implement either 32/64 subclasses as you suggest if there's prim support, or a #getDetailedPlatformInfo dependent on FFI to fetch more specific details like 32/64 bit, actual windows version, etc.. -- Sent from: http://forum.world.st/Pharo-Smalltalk-Developers-f1294837.html