Unknown instruction: ARG

[snobear]

By default, Circle CI currently uses Docker 1.8 which doesn’t support the ARG Dockerfile command. I was able to use Docker 1.10 though with this info and my build is running fine now:

Docker 1.10.0 is available (Beta)

Note: this post is deprecated. We recommend all new project that require up-to-date Docker support use CircleCI 2.0: https://circleci.com/docs/2.0/ We now have Docker 1.10.0 working on CircleCI. You just need to add the following to your circle.yml. machine: pre: - curl -sSL https://s3.amazonaws.com/circle-downloads/install-circleci-docker.sh | bash -s -- 1.10.0 services: - docker Note As you may already know, we apply a small patch to Docker to run on CircleCI build machines. …