Homebrew

Installing with brew is the preferred way to install for most use-cases. Homebrew installs the tool globally, and is updated with every release.

Environment Variables

Exporting the following will peg you to a specific version of php for your instance, using homebrew. This is a makeshift approach that requires direnv or the like, in the future the tool will abstract this away for you.

export MAGECLI_PHP_VERSION=8.1.6
export MAGECLI_PHP_BIN=/opt/homebrew/Cellar/php/$MAGECLI_PHP_VERSION/bin/
export PATH=$MAGECLI_PHP_BIN:$PATH%

Installation

Installing PHP with brew is easy, just trigger:

brew install php@8.1

If you run brew link php@8.1 this will set it as the system-wide default. This seems like it should be fine, but keep in mind tools like magento-cloud require PHP 7.4 at the time of this writing so having the system-wide as that version is usually simpler. See the environment variables section to set this per-directory.