ServerPilot uses its own PHP builds so you can have multiple versions of PHP on a server independent of what Ubuntu ships.
If you try to use composer, you'll likely experience the following error.
ubuntu@precise64:~$ composer
No command 'composer' found, did you mean:
Command 'compose' from package 'mime-support' (main)
composer: command not found
The ServerPilot composer executables are named like composer5.X-sp.
ubuntu@precise64:~$ composer5.4-sp -h
______
/ ____/___ ____ ___ ____ ____ ________ _____
/ / / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___/
/ /___/ /_/ / / / / / / /_/ / /_/ (__ ) __/ /
\____/\____/_/ /_/ /_/ .___/\____/____/\___/_/
/_/
Composer version 1.0.0-alpha7
For more information, see What ServerPilot Installs, Why ServerPilot Installs Its Own Nginx, Apache, and PHP Packages, and How to Use the PHP CLI.