Article Composer Monorepo Plugin (previously called Fiddler)

I have written about monorepos in this blog before, presented a talk about this topic and released a standalone tool called "Fiddler" that helps integrating Composer with a monolithic repository.

At the beginning of the year, somebody in #composer-dev IRC channel on Freenode pointed me in the direction of Composer plugins to use with Fiddler and it was an easy change to do so.

With the help of a new Composer v1.1 feature to add custom commands from a plugin, Fiddler is now "gone" and I renamed the repository to the practical beberlei/composer-monorepo-plugin package name on Github. After you install this plugin, you have the possibility to maintain subpackages and their dependencies in a single repository.

$ composer require beberlei/composer-monorepo-plugin

To use the plugin add monorepo.json files into each directory of a subpackage and use a format similar to the composer.json to add dependencies to a.) external composer packages that you have listed in your global Composer file b.) other subpackages in the current monorepo. See this example for a demonstration:

    "deps": [
    "autoload": {
        "psr-0": {"Bar": "src/"}

This subpackage here defined in a hypothetical file components/Bar/monorepo.json has dependencies to Symfony HTTP foundation and another subpackage Foo with its own components/Foo/monnorepo.json. Notice how we don't need to specify versions (they are implicit) and import other dependencies using the relative path from the global composer.json.

The monorepo plugin is integrated with Composer, so every time you perform install, update or dump-autoload commands, the subpackages will be updated as well and each get their own autoloader that can be included from vendor/autoload.php relative to the subpackages root directory as usual.

Published: 2016-05-28 Tags: #Monorepos #Composer