Xenial as the default build environment

As announced two weeks ago, we've started incrementally updating the default build environment to Ubuntu Xenial 16.04.

Right now, 5% of the repositories building that do not explicitly specify an Operating System, os: key, or an Ubuntu Linux distribution, via the dist: key are now being routed to Ubuntu Xenial 16.04 instead of Ubuntu Trusty 14.04.

We'll continue increasing the percentage of repositories using the new default throughout the next few weeks and posting updates here as we move forward.

To test how Xenial will work for you, please specify it directly with

dist: xenial.

Make sure to bring any questions you might have to the Travis CI Community Forum: Xenial.

If you'd like to stay on Trusty, that's also an option, you can pin your repository to continue using Ubuntu Trusty 14.04, by specifing dist: trusty in your .travis.yml file.