Leveraging Composer

Composer is the defacto standard to handle PHP application dependencies, as well as providing mechanisms to keep them up-2-date. Learn how to integrate Composer into your development workflow with fortrabbit.


It's recommended that you have Composer running in your local development environment as well.

Composer with Git

Local         fortrabbit deploy service           Your fortrabbit App
┌────────┐    ┌────────────┐  ┌────────────┐      ┌──────────────┐
│        │    │            │  │            │      │              │
│  Git   ├────▶  Git repo  ├──▶  Composer  ├──────▶   webspace   │
│        │    │            │  │            │      │              │
└────────┘    └────────────┘  └────────────┘      └──────────────┘

The above drawing illustrates the fortrabbit architecture. When you deploy with Git, Composer will run automatically along within the deployment process on fortrabbit. So, when you git push:

  1. the Git repo will be updated
  2. a composer install will be triggered
  3. new files will be distributed to the webspace

Advanced usage

The vendor folder

The vendor folder should NOT be in Git: Make sure that folder is included in your .gitignore file. This directory is created by Composer within your project locally and contains all the packages you are using locally. Make sure that both the composer.lock file and the composer.json file are present and part of Git.

Composer in the deployment file

You can fine-tune your deployment behavior and aspects of Composer in the deployment file. See the options under the composer: keyword here.

Alternative locations

If your composer.json and composer.lock files are not on the top level, then they will be ignored by the deployment. However, you can use the pre directive from the deployment file to set up a custom composer run in a different directory.

Here is an example which assumes that your composer.* files are within the folder sub-folder:


version: 2

# execute alternate composer run before anything
pre: /usr/local/bin/composer install --prefer-dist -d sub-folder

# make sure the new vendor folder is sustained during deploys
  - sub-folder/vendor

Private repositories in Composer

You need to add the private repositories into your composer.json file? Read on here.

Composer from SSH

Universal Apps only: While we highly recommend leveraging Composer via the Git deployment (see above), you can also execute Composer when logged in via SSH. Please note that this should only be done in certain edge cases.

$ ssh {{ssh-user}}@deploy.{{region}}.frbit.com
$ composer install

This way Composer will be executed within your App's web delivery environment, which is not optimized for such tasks.

Please don't use composer update as this might cause Composer to hit the App's memory limits.

Composer 1 on the App

We do not actively update the composer version in your ssh environment, you can control it on your own:

$ composer selfupdate --2

Please mind, the composer version in the git (deployment) environment is always up-to-date and managed by us.


Memory problems with Composer

The most common Composer issue is, when users are running into memory problems when trying to execute composer install while logged in via SSH here. The general answer on that is: Please don't. Use Composer together with Git deployment as described above.

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