I am following the installation instructions from this article but I get a bad substitution error from zsh when executing this command: What am I supposed to change for zsh? Answer ${DISTRIB_ID,,} is a Bash-specific parameter expansion to lowercase the value of the variable. https://askubuntu.com/a/383360/25077 suggests ${(L)DISTRIB_ID} as a corresponding operation in Zsh. But there is no real reason for