Travis CI will now allow developers to test open source software on ARM-based architectures under a just announced alpha program.

The CI vendor said it has been working with Canonical, ARM and cloud provider Packet “for the past few months” on the programme, the first fruits of which are free ARM-based builds.

These will use “LXD-powered containerization” to run the builds. LXD is a Canonical-led container management project.

The project is still in its early stages, and is restricted to open source projects, though Travis added, “if you’d like to test private projects, please send us a message in the forum.”

Even so, capacity is limited, and “Initial testing capacity starts at around 60 concurrent jobs so please keep this in mind while testing Arm-based builds.”

At the same time, it said, “Packet is delivering the Arm64 (Armv8 compliant) infrastructure and it has been adjusted to ensure stable build times. Please grant us additional time to react when increasing capacity as it requires both companies to align.”

The use of LXD is a bit of a departure for Travis, which took some time to explain the technology. Like Docker, it evolved from the Linux Container runtime, Travis said. However, LXD “allows for system containers or a ‘lightweight vm-like container’” and gives a “full OS” inside a container, along with VM-like semantics so they can be easily operated and managed. Doing the same thing with Docker would mean enabling specific systems processes each time a Docker container is run, which would increase complexity and execution times.

Travis clearly likes this approach, as “we are looking at expanding our usage of LXD containers for the existing build setups at Travis CI.”

This is one of the bigger announcements from Travis this year, other than its being absorbed into private equity backed software conglomerate Idera. User concerns that the company might lose its mojo weren’t helped by a massive outage in March in the wake of reported large scale layoffs at the company.