Buildkite is a hosted CI system with a limited feature set. These two tricks will help you seemlessly run buildkite scripts in Concourse CI:

Set the input's path to .

Because the only input to a Buildkite's job is a repo at a commit, buildkite starts the build in the context of the root of the repo under build as a starting working directory. This is in contrast to Concourse, which starts you in a parent build directory with multiple possible input and output subdirectories.

Example task config looks as follows:

  - task: build
    config:
      platform: linux
      image_resource:
        type: registry-image
        source:
          repository: alpine
      params:
        PACKAGE_NAME: mypackage
      inputs:
        - name: code-repo
          path: .
      outputs:
        - name: tarball
      run:
        path: buildkite/mybuildscript.sh

Replace buildkite-agent artifact * with resources

In buildkite, downloading and uploading "artifacts" is done through the buildkite-agent CLI, for example:

buildkite-agent artifact download image-id/* .

conversely:

buildkite-agent artifact upload "vm-ip/vm-ip.txt"

To mimick this behavior in buildkite create a docker image with an empty buildkite-agent script in $PATH, for example

#!/bin/sh
# contents of /bin/buildkite-agent
exit 0

and replace artifact downloads/uploads with respective inputs and outputs. Example job definition:

  - get: code-repo
  - task: build
    config:
      platform: linux
      image_resource:
        type: registry-image
        source:
          repository: alpine
      inputs:
        - name: code-repo
          path: .
        - name: image-id
      outputs:
        - name: vm-ip
      params:
        PACKAGE_NAME: mypackage
      run:
        path: buildkite/mybuildscript.sh
  - put: vm-ip
    params:
      file: vm-ip/vm-ip.txt