Documentation: http://devops.wcm.io/conga/definitions/aem/
Issues: https://wcm-io.atlassian.net/projects/WDCONGA
Wiki: https://wcm-io.atlassian.net/wiki/
Continuous Integration: https://travis-ci.org/wcm-io-devops/conga-aem-definitions
If you want to build from sources make sure you have configured all Maven Repositories in your settings.xml.
See Travis Maven settings.xml for an example with a full configuration.
Then you can build using
mvn clean install