Build development environments from a Dockerfile on Docker, Kubernetes, and OpenShift. Allow developers to modify their environment in a tight feedback loop.

• Supports devcontainer.json and Dockerfile
• Cache image layers with registries for speedy builds
• Runs on Kubernetes, Docker, and OpenShift

The easiest way to get started is to run the envbuilder Docker container that clones a repository, builds the image from a Dockerfile, and runs the $INIT_SCRIPT in the freshly built container.

/tmp/envbuilder is used to persist data between commands for the purpose of this demo. You can change it to any directory you want.

docker run -it --rm \
    -v /tmp/envbuilder:/workspaces \
    -e GIT_URL=https://github.com/coder/envbuilder-starter-devcontainer \
    -e INIT_SCRIPT=bash \
    ghcr.io/coder/envbuilder

Edit .devcontainer/Dockerfile to add htop:

$ vim .devcontainer/Dockerfile

- RUN apt-get install vim sudo -y
+ RUN apt-get install vim sudo htop -y

Exit the container, and re-run the docker run command... after the build completes, htop should exist in the container! 🥳

envbuilder uses Kaniko to build containers. You should follow their instructions to create an authentication configuration.

After you have a configuration that resembles the following:

{
  "auths": {
    "https://index.docker.io/v1/": {
      "auth": "base64-encoded-username-and-password"
    }
  }
}

base64 encode the JSON and provide it to envbuilder as the DOCKER_CONFIG_BASE64 environment variable.

GIT_USERNAME and GIT_PASSWORD are environment variables to provide Git authentication for private repositories.

For access token-based authentication, follow the following schema (if empty, there's no need to provide the field):

If using envbuilder inside of Coder, you can use the coder_git_auth Terraform resource to automatically provide this token on workspace creation:

resource "coder_git_auth" "github" {
    id = "github"
}

resource "docker_container" "dev" {
    env = [
        GIT_USERNAME = coder_git_auth.github.access_token,
    ]
}

Cache layers in a container registry to speed up builds. To enable caching, authenticate with your registry and set the CACHE_REPO environment variable.

CACHE_REPO=ghcr.io/coder/repo-cache

Each layer is stored in the registry as a separate image. The image tag is the hash of the layer's contents. The image digest is the hash of the image tag. The image digest is used to pull the layer from the registry.

We don't support mounts, features, and many other primitives of devcontainer.json. We support the following:

• image
• build
• runArgs
• workspaceFolder