title: CircleCi: Couldn't connect to Docker daemon at http+docker://localhost
body: <p>In my Node.js project tests I'm starting <code>docker-compose</code> via <code>child_process.spawn</code>.</p>
  
  <p>When running CircleCi, the build fails with this error:</p>
  
  <pre><code>Couldn't connect to Docker daemon at http+docker://localhost - is it running?
  </code></pre>
  
  <p>This is the <code>.circleci/config.yml</code>:</p>
  
  <pre><code>version: 2
  jobs:
    build:
      docker:
        # specify the version you desire here
        - image: circleci/node:8
  
      working_directory: ~/repo
  
      steps:
        - checkout
  
        # Download and cache dependencies
        - restore_cache:
            keys:
            - v1-dependencies-{{ checksum "package.json" }}
            # fallback to using the latest cache if no exact match is found
            - v1-dependencies-
  
        - run: npm install
  
        - save_cache:
            paths:
              - node_modules
            key: v1-dependencies-{{ checksum "package.json" }}
  
        # run tests!
        - run: npm test
  </code></pre>