From Amazon to VMware, via Docker, Google, Microsoft and Red Hat, more than 20 of the biggest names in technology have piled in behind a major new non-profit initiative to establish container standards and specifications.
The Open Container Project, created under the auspices of the Linux Foundation, aims to institute core runtime and format standards that will foster the current high levels of innovation in containers, while protecting users against lock-in and market fragmentation.
As a first step, Docker has donated the code for its software container format and runtime, along with the associated specs, to the project. Announced in December, the App Container spec - known as appc - initiative, including founding member CoreOS, is also joining the new coalition.
"There's been a lot of activity around Docker and the container space in general, and we and others in the industry feel it's time to define the box a bit more precisely so that we stop arguing about the shape of the box - and where the hooks and holes go - and can start focusing on innovating at higher levels," Docker CEO Ben Golub said.
The full list of Open Container Project signatories consists of: Amazon Web Services, Apcera, Cisco, CoreOS, Docker, EMC, Fujitsu, Goldman Sachs, Google, HP, Huawei, IBM, Intel, Joyent, Linux Foundation, Mesosphere, Microsoft, Pivotal, Rancher Labs, Red Hat and VMware.
Docker is the most popular technology for automating the creation and deployment of apps in containers - a lighter-weight form of virtualisation. The idea is to free developers from software and infrastructure dependencies, cutting costs and creating efficiencies in the process.
"Docker is so ubiquitous and such a de facto standard, that we're starting with the donation of the Docker container format and the Docker container runtime," Golub said.
"We're donating that code into this organisation. It's a fairly minimal set of code that's ready for everybody to coalesce around. We're not trying to define a big stack on top of it. Ninety percent of what Docker does is outside of this. But everybody said, 'Hey, we want to get on the same page and we want to start with the thing that's the most ubiquitous - and that's Docker'."
The Open Container Project said the rapid proliferation of container development projects and tools has created the impetus for the new initiative.
According to Docker, more than three million developers are using Docker, creating about 140,000 Docker-based apps that have been downloaded over 500 million times.
"People have jumped into containers in a big way and the last thing people want is to have the foundation of that fragmented. But of course, if we are going to agree on a standard container, then that can't really be owned by anybody," Golub said.
"So I think we've done it the right way. We've let the market choose first what their de facto choice is. Now we want to make sure that, as vendors and as users and as companies, we all band together to say, 'Let's make this what we agree on. Let's not argue about the width of the train tracks anymore. Let's spend our time worrying about how to build faster trains'."
The Open Container Project will have three levels of activity. The first will be the technical leadership, consisting of the leaders of the libcontainers project donated by Docker, along with two experts from appc - one from Red Hat and one from CoreOS.
A neutral technology oversight board, consisting of practitioners rather than vendors, will be put in place to ensure the technical team is operating in an independent and impartial fashion.
At the top level is the Linux Foundation itself, which will deal with issues such as trademarks and fiduciary oversight.
The Open Container Project said it will manage the transition of the Docker technology from an insider standard into an open industry standard.
The Docker project will continue to maintain the Docker client, all platform tooling, and all Docker orchestration capabilities built on top of the donated technologies. Other projects and companies will also be able to build technologies on the new initiative's format and runtime.
With a charter to establish a set of common, minimal standards around container technology, the project said it will ensure its image format is backwards-compatible with those of Docker and appc, and will include efforts to harmonise with other container projects in the community.
The new initiative will be founded on three guiding principles: standards will not be bound to higher-level constructs, such as a particular client or orchestration stack; they won't be tightly associated with any particular commercial vendor or project: and they will be portable across a wide variety of operating systems, hardware, CPU architectures, and public clouds.
As well as backwards-compatibility, minimalism and openness, core values for the Open Container Project consist of security, portability and composability.
Those involved in the project expect it to be set up within three months, together with the publication of a draft specification based on the technology donated by Docker.
"What we've done is we've got everybody who's associated with this to sign a letter of intent, outlining the basics, the guidelines, what we're all trying to do. Because we're going to be forming this under the auspices of the Linux Foundation, a lot of the heavy lifting of setting up and the governance have already been done," Golub said.
"We're expecting that in a few weeks all the final legal work will have been done and we can be officially started. But in the meantime we're launching the website with the code already there. As usual, developers don't wait for lawyers."
Golub said the establishment of the Open Container Project will have little impact on Docker's day-to-day activities beyond the ownership of the core elements residing in a different organisation.
"For us, we've always believed that the best code is composable and you don't build one big monolithic block. Instead, you have small pieces that do their job well and which can operate independently," he said.
"So, we're taking an important but small piece of what Docker is and saying, 'This is ready to be specified and hardened and not changed so much, so that the rest of what we work on can innovate more rapidly'.
"What this also means is that we can go to the huge numbers of users that we have, both commercial and open source, and say, 'Don't worry anymore. You can jump into using Docker or any other tool without worrying that you're locked into any vendor, including Docker'."