Github will no longer support travis.ci as a github service in the same way after Jan 1, 2019 This will impact the mechanics of how the mac version of Seamly2D is built in the pipeline.
If you care to read more on this subject, please see:
The schedule published in the github documentation includes the following milestones
May 31, 2018: Submit your intentions for migrating or replacing your GitHub Service. October 1, 2018: GitHub discontinues allowing users to install services. GitHub Services will be removed from the GitHub.com UI. January 31, 2019: GitHub stops delivering installed services' events on GitHub.com.
This is the first time I have become aware of this timetable. I will continue research to find out how to implement this transition to prevent an interruption in the ability to deliver a Mac build.
If individuals wish to volunteer to assist in creating this new interface please contact @kmf. This work will be accomplished during December and must be on line by January 31, 2019.