Using GitHub forks or local Git repositories with Composer

For two weeks I have been heavily developing a new web application based upon Laravel. Tonight I searched for an easy filtering solution like Zend_Filter so that the request strings are automagically trim’d, lowercased, and so on. Lucky me, the repository is available with a composer.json but latest commit from 2013 is not compatible with Laravel 5.1. The compatibility fix would be trivial: editing two files in the composer.json and it is done. But how can I use my own fork on GitHub or my local cloned repository?

I learned, that I can add a repository reference to the composer.json of my application:

"repositories": [
			"type": "vcs",
			"url": ""

Additionally, I have to specify my development branch which contains the Laravel 5.1 fix (laravel51):

    "require": {
        "php": ">=5.5.9",
        "laravel/framework": "5.1.*",
        "laracasts/flash": "~1.3",
        "cocur/slugify": "dev-master",
        "rmasters/filter": "dev-laravel51"

It is important that the Git branch is named laravel51 and not dev-laravel51, otherwise you will receive an error like

Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - The requested package rmasters/filter could not be found in any version, there may be a typo in the package name.

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see for more details.

Read for further common problems.

Another neat feature is that Composer supports local repositories without any problems. During testing I changed my repository to

	"repositories": [
			"type": "vcs",
			"url": "c:/ckl/projects/github/filter"

and had no longer to push my changes to the remote repository. The code has to be committed to local branch, of course.