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Modern, fast, efficient & on-demand Docker builds for all your application needs

works with GitHub GitLab BitBucket
Shut down as of August 20th

How does it work?

Try it with any public git repo!

$ docker run ctr.run/github.com/undefinedlabs/hello-world:master

Why Ctr.run?

We built Ctr.run to stop wasting time and money building, pushing, and storing container images that never get used. To speed up all container builds with automatic caching and parallelism that works everywhere: locally, across CI providers, and container runtimes.

And to eliminate the guesswork of what :tag to pull to see the latest changes in master or a feature-branch.

Using ctr.run is easy, simply docker run the git commit, branch or tag you need, when you need it:

Automatic build caching

Git-inherited authorization

Parallel build step execution

On-demand builds

Works with k8s and other container runtimes

JIT (just-in-time) Docker Build

Execute docker run ctr.run/github.com/... and ctr.run will automatically build your container image – faster than you ever imagined possible.

The fastest builder West of the Mississippi

ctr.run is built using the most innovative, efficient and fastest container build system in the world: buildkit. Thanks to buildkit, build steps are automatically cached and parallelized, and all builds are incremental by default.

Internet-scale caching

ctr.run uses CDN-based edge caching to guarantee availability and bring you the fastest pulls anywhere around the globe. Take that and rewind it back.

Efficiency FTW

Stop building and pushing images that you'll never use. It's common to build and push to a registry as part of CI, but many of these images rarely get used. ctr.run only builds the container images you'll actually run.

Deprecate build & push from your toolchain

Imagine there's a new commit to try out. It has a Dockerfile, and there's an image in DockerHub, but it's from last week's release, what do you do?

docker run ctr.run/github.com/namespace/repo[:commit-hash, branch-name, tag-name]

Works wherever your container needs take you

Kubernetes ◇ AWS ECS ◇ AWS Fargate ◇ AKS ◇ GKS ◇ Github Actions ◇ Jenkins ◇ CircleCI ◇ Docker for Mac/Windows ◇ Okteto ◇ k3s ◇ OpenShift ◇ Pivotal Cloud Foundry ◇ and everywhere else!