title: Upgrade or install Ghostscript 9.21 in docker image node:7
body: <p>I'm installing Ghostscript into a docker image and want to use it with ghostscript4js which requires for some functionality at least Ghostscript 9.21.</p>
  <p>I'm using this in my docker file which installs Ghostscript 9.06</p>
  <pre><code>    FROM node:7
  
  ARG JOB_TOKEN
  
  RUN apt-get update &amp;&amp; \
      apt-get install -y pdftk
  
  ENV APP_DIR=&quot;/usr/src/app&quot; \
      JOB_TOKEN=${JOB_TOKEN} \
      APP_DIR=&quot;/usr/src/app&quot; \
      GS4JS_HOME=&quot;/usr/lib&quot;
  
  
  COPY ./ ${APP_DIR}
  
  # Step 1: Install App
  # -------------------
  WORKDIR ${APP_DIR}
  
  # Step 2: Install Python, GhostScript and npm packages
  # -------------------
  ARG CACHE_DATE=2017-01-01
  RUN \
    apt-get update &amp;&amp; \
    apt-get install -y build-essential make gcc g++ python python-dev python-pip python-virtualenv &amp;&amp; \
    apt-get -y install ghostscript &amp;&amp; apt-get clean &amp;&amp; \
    apt-get install -y libgs-dev &amp;&amp; \
    rm -rf /var/lib/apt/lists/*
  
  
  RUN npm install
  
  # Step 3: Start App
  # -----------------
  CMD [&quot;npm&quot;, &quot;run&quot;, &quot;start&quot;]
  </code></pre>
  <p>How do I install or upgrade to a higher Ghostscript version in a docker image?</p>