When installing packages for Python, Ruby or other similar languages, always avoid installing packages alongside packages installed with the systems package manager.
Use pipsi to install python tools, and virtualenv/tox to install project dependencies. If it’s necessary to install packages into a global namespace, use
pip install --user. v and virtualenvwrapper are useful tools to manage a set of Python virtual environments.
Python 2.7 is a required package on Debian and RHEL systems, and often comes with python modules installed via the system’s package manager. It’s a really bad idea to install python packages that aren’t managed by the system package manager into the system’s Python installation. In particular, pip may break things on some versions of Debian/Ubuntu due to the way the Debian packages are distributed.
gem install --user-install to install gems into your home directory instead of the systems folders. rvm can be used to install and manage multiple Ruby versions. bundler can be used to manage project dependencies.
Uninstall all Ruby gems with:
gem list | cut -d" " -f1 | xargs sudo gem uninstall -aIx