CircleCI 2.0 Jekyll build and Firebase deploy

config.yml

### Taken from https://github.com/Hyperparticle/hyperparticle.github.io/blob/2365749469b1eea3e8c4b18af24a4865fc426fd3/.circleci/config.yml

# Javascript Node CircleCI 2.0 configuration file
#
# Check https://circleci.com/docs/2.0/language-javascript/ for more details
#
version: 2
jobs:
  build:
    docker:
      # specify the version you desire here
      - image: starefossen/ruby-node:2-8
      
      # Specify service dependencies here if necessary
      # CircleCI maintains a library of pre-built images
      # documented at https://circleci.com/docs/2.0/circleci-images/
      # - image: circleci/mongo:3.4.4

    working_directory: ~/repo

    steps:
      - checkout

      # Download and cache dependencies
      - restore_cache:
          keys:
          - v2-dependencies-{{ checksum "Gemfile.lock" }}
          # fallback to using the latest cache if no exact match is found
          - v2-dependencies-

      - run:
          name: Ruby dependencies
          command: bundle install

      - run:
          name: Node dependencies
          command: npm install -g firebase-tools@3.9.1 --unsafe-perm

      - save_cache:
          paths:
            - /usr/local/bundle
            - /usr/local/lib/node_modules
          key: v2-dependencies-{{ checksum "Gemfile.lock" }}

      - run:
          name: Build
          command: bundle exec jekyll build --verbose
      
      - run:
          name: Test
          command: bundle exec htmlproofer ./_site --check-html --disable-external
      
      - run:
          name: Deploy
          command: firebase deploy --token=$FIREBASE_TOKEN --non-interactive