Hello, Guix's default skeletons put "source /etc/profile" into ~/.zlogin. But /etc/profile resets the PATH environment variable, exports many other environment variables, and source /etc/bashrc. According to http://zsh.sourceforge.net/Intro/intro_3.html .zlogin is sourced after .zshrc and should not be used for alias definitions, options, environment variable settings, etc. Especially "as a general rule, it should not change the shell environment at all". I think it's better to source /etc/profile from ~/.zprofile.
Meiyo Peng