Use multiple php versions on macOS / Linux

The end goal#

• Have multiple versions of php installed
• Use php 7.x when you run php
• Use php 8.x when you run php8

The Steps#

MacOS#

I prefer this over brew solutions with link and unlink.

• Install both the default php package and the older php7.4 package

  # Install php (defaults to version 8).
  brew install php
  
  # Install older php 7.4.
  brew install php@7.4
  

• Make php 7.4 the default

  # Unlink php8.
  brew unlink php
  
  # Double check php 7.4 is linked (this will set php7.4 as the default)
  brew link php@7.4
  

• Create an extra symlink for php 8

  # Create a symlink in /usr/local/bin.
  ln -s /usr/local/opt/php/bin/php /usr/local/bin/php8
  

• Remove any manual php $PATH setups in your .bashrc or .zshrc (or equivelent). It may look like this.

  # .bashrc or .zshrc or equivelent
  
  # Remove this line!
  export PATH="/usr/local/opt/php@7.4/bin:$PATH"
  

Linux (using pamac)#

• Install both default php package and older php7.4 package. The ArchWiki will always have the latest instructions but this what I did at the time.

  # Install php (defaults to version 8).
  pamac install php
  
  # Install older php 7.4.
  pamac install php74
  

• Setup symlinks.

  # Setup php 8 as the version to be used when you run "php8".
  sudo ln -s /usr/bin/php /usr/local/bin/php8
  
  # Setup php 7.4 as the default version to be used.
  sudo ln -s /usr/bin/php74 /usr/local/bin/php
  

The Result#

• Output of php -v

  $ php -v
  PHP 7.4.27 (cli) (built: Dec 16 2021 18:14:46) ( NTS )
  Copyright (c) The PHP Group
  Zend Engine v3.4.0, Copyright (c) Zend Technologies
  with Zend OPcache v7.4.27, Copyright (c), by Zend Technologies
  

• Output of php8 -v

  $ php8 -v
  PHP 8.1.1 (cli) (built: Jan  8 2022 08:25:03) (NTS)
  Copyright (c) The PHP Group
  Zend Engine v4.1.1, Copyright (c) Zend Technologies
  with Zend OPcache v8.1.1, Copyright (c), by Zend Technologies