My home server was running CentOS 6, and this was getting a bit long in the tooth:
- The libwww-perl version that ships in CentOS 6 does not handle HTTPS certificates in a secure way. This was only fixed in LWP version 6. There's almost no chance of LWP getting rebased, since that module is part of Perl core, and it's so late in the RHEL 6 lifecycle.
- The Python version (2.6) is so old that many Python apps no longer support it. The one I was particularly interested in was Sigal to generate my own photo gallery for my family.
I tried using the Python 3.3 software collections, and this worked well to get Sigal running in a Python 3.3 virtualenv.
For Perl, I didn't want to deal with SCLs, because my application has a long dependency chain, and I would need to rebuild a lot of SCL-style RPMs to get my app to work. I could just use the "cpan" tool (similar to virtualenv/pip), but I wanted to avoid the security and stability issues associated with using an essentially random snapshot in time of modules that I grabbed from upstream. I like the fact that Bugzilla is a central place to track CVEs, and I like the waiting period in epel-testing and the possibility for community collaboration there, etc.
The idea of using multiple SCLs and lots of non-packaged upstream modules was what pushed me to just bite the bullet and update to CentOS 7. CentOS base + CentOS extras + EPEL 7 already had all the deps for Sigal, except python-pilkit. I buckled down and learned just enough Python packaging techniques in order to package python-pilkit and python-sigal. And the best part is that the packages actually work on my new EL7 system (knock on wood).