Sure, https://perldoc.perl.org/perlpolicy.html#BACKWARD-COMPATIBIL... that’s the policy for the language itself, but as it mentions there it’s considered generally a “community” virtue. I wasn’t programming back in 02 so I’m sure it was extremely different (and the source I’ve read from modules from that era is pretty frightening. Any major framework or generally used module will try to maintain backwards compatibility at least as far as documented behavior. I’ve never come across the kind of stuff I see all the time with node and go and python; package maintainers changing parameters and such because they weren’t happy with the original API.