Sort composer.json based on the well-known composer.json keys. List and order of keys is derived from composer docs.
Install mleko/wingman as global package
$ composer global require mleko/wingman
Format specific composer.json file
$ wingman format /project-dir/composer.json
Formatting file: /project-dir/composer.json
Format composer.json in current directory
$ cd /project-dir
$ wingman
Formatting file: ./composer.json
Install mleko/wingman as dependency
$ composer require --dev mleko/wingman
$ vendor/bin/wingman --register
Register wingman in file: ./composer.json
Wingman registered
Formatting file: ./composer.json
composer.json will be reformatted after every package update.