Default behavior dictates the following order for ZSH startup files:

• /etc/zshenv
• ~/.zshenv
• /etc/zprofile (if login shell)
• ~/.zprofile (if login shell)
• /etc/zshrc (if interactive)
• ~/.zshrc (if interactive)
• /etc/zlogin (if login shell)
• ~/.zlogin (if login shell)

Notes:

• zshenv is the place to set environment variables
• zshrc is the place for aliases, functions etc

Setting environment variables in zshenv means that they'll be present for non-interactive uses (think cron commands). This is what you want.

At least Debian/Gentoo/Arch ship an /etc/zprofile which sets (not adds to, sets) a value for $PATH. Because this file is sourced after ~/.zshenv, any value you may have set there is overridden.

Possible solutions:

• Move the system /etc/zprofile to /etc/zshenv
• Set your path in ~/.zprofile, not ~/.zshenv

Neither are great.

Moving /etc/zprofile to /etc/zshenv means whatever commands are there are now invoked for every shell (rather than once at login). This is wasteful, there's no need to (re)set your locale in every shell every time.

Setting environment variables in zprofile means they'll be set once (on login) and inherited by all shells invoked directly or indirectly. This mostly works. The variables won't be present for (e.g.) cron commands and any exports must be duplicated in your crontab.

References:

• ZSH Startup/Shutdown Files: http://zsh.sourceforge.net/Doc/Release/Files.html
• Arch bug: https://bugs.archlinux.org/task/35966
• Gentoo bug: https://bugs.gentoo.org/show_bug.cgi?id=19924