Can I add maven repositories in the command line?

I'm aware I can add maven repositories for fetching dependencies in ~/.m2/settings.xml. But is it possible to add a repository using command line, something like:

mvn install -Dmaven.repository=http://example.com/maven2

The reason I want to do this is because I'm using a continuous integration tool where I have full control over the command line options it uses to call maven, but managing the settings.xml for the user that runs the integration tool is a bit of a hassle.

You can do this but you're probably better off doing it in the POM as others have said.

On the command line you can specify a property for the local repository, and another repository for the remote repositories. The remote repository will have all default settings though

The example below specifies two remote repositories and a custom local repository.

mvn package -Dmaven.repo.remote=http://www.ibiblio.org/maven/,http://myrepo 
  -Dmaven.repo.local="c:\test\repo"

One of the goals for Maven't Project Object Model (POM) is to capture all information needed to reliably reproduce an artifact, thus passing settings impacting the artifact creation is strongly discouraged.

To achieve your goal, you can check in your user-level settings.xml file with each project and use the -s (or --settings) option to pass it to the build.