[ilikepi]

For some time now, in the default configuration, `brew upgrade` is run automatically any time you run `brew install`. You have to set HOMEBREW_NO_AUTO_UPDATE to disable this behavior.

EDIT: whoops, that was incorrect. It's actually `brew update` that is run automatically, which updates Homebrew itself plus all of its formulae. However, I think often the effect can't be similar. If formulae are updated, and the new package you're trying to install shares a dependency with other packages, the dependency will be automatically updated as part of the install process. I'm not sure if this can also trigger an update of an existing leaf package though.

[bargsteen]

Yes, figuring this out I created an alias a few months ago. #LifeImproved :D

Add this to your .zshrc or equivalent (f for fast):

alias brewf="HOMEBREW_NO_AUTO_UPDATE=1 brew"