Sometimes you may want to use an external project from within your main repository, eg. a library that will generate code in your web app. Git addresses this issue with submodules that allow you to deploy changes from both main and external repositories.
What you need to know about submodules in Buddy:
Deployments from submodules are enabled in Buddy by default. You can turn them off in the right column in Pipelines
HTTPS submodules require no additional configuration. However, the submodule must be a repository within the same integration to work. For example, if your repository is hosted on GitHub you can only use repositories from the currently synchronized GitHub account.
SSH submodules are much less restritive. For example, you can keep a private Bitbucket repository in your GitHub repository as a submodule. To activate a private SSH submodule you must authenticate Buddy into it by adding a public SSH key (eg. as a deployment key). You will find the key by clicking the Submodules in the right column of the Pipelines tab. The key is different for each project.