I don't use RVM anymore and don't know whether this specific bug was fixed. The point of my example wasn't "RVM sucks because I once encountered a bug". The poi

I don't use RVM anymore and don't know whether this specific bug was fixed. The point of my example wasn't "RVM sucks because I once encountered a bug". The point was that RVM's model of tampering with the user's environment in a global way is problematic because when bugs inevitably arise, as they do in all software, they break unrelated software in ways that an inexperienced user wouldn't be able to tie to RVM. This is what I think your Python example below misses. If Python is slow because it doesn't have a JIT and that causes someone's program to run too slowly, they can see that the problem is that Python is slow. Python's lack of a JIT would never cause "man traceroute" to stop working in a shell session where the user hasn't done anything related to Python and couldn't possibly guess that Python is the culprit.