How to use Homebrew on a Multi-user MacOS Sierra Setup

I have a Mac that is shared between two engineers. Both have separate user accounts. Both need to run brew update and brew install... occasionally.

How do I set this up without getting errors like: /usr/local must be writable!?

Yeah, I could have UserA take over the permissions of /usr/local every time he wants to use brew (and same with UserB), but that seems like a lot of unnecessary trouble.


  • You can also change the group permissions to admin or another group that both of your users are in:

    chgrp -R admin /usr/local
    chmod -R g+w /usr/local

    Original source:


    In macOS High Sierra you can't change the owner, group or permissions of /usr/local. So you have to change the group and permissions of the subfolders:

    chgrp -R admin /usr/local/*
    chmod -R g+w /usr/local/*

    UPDATE September 2018, High Sierra 10.13.6

    1. Determine the path of the brew prefix, ie. the path that will be used to store files related to working with homebrew
    2. Check that all users on the system who need access to brew are in the admin group
    3. Optional Add a user to the admin group if a user needs access to brew

      Will require access / privileges to use the sudo command

    4. Set the brew prefix path to be recursively owned by the admin group
    5. Set the brew prefix path to be recursively writable by all users who are in the admin group
    6. Verify the permissions of the brew prefix
    7. brew 🍻

    echo $(brew --prefix)
    echo $(groups $(whoami))
    sudo dseditgroup -o edit -a $(whoami) -t user admin
    sudo chgrp -R admin $(brew --prefix) 
    sudo chmod -R g+rwX $(brew --prefix)
    ls -lah $(brew --prefix)