anchor.diff:  RUN chown testbot /home/testbot
   
   # install chrome
  -ENV CHROME_VERSION stable
  -RUN /tmp/install-chrome.sh
  +RUN wget https://dl.google.com/linux/direct/$CHROME_DEB
  +RUN dpkg --install --force-overwrite --force-confdef $CHROME_DEB || sudo apt-get -y -f install
  +
  +# start the virtual framebuffer
  +RUN /sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_99.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :99 -ac -screen 0 1280x1024x16
  +
  +# run up testbot
  +RUN git clone https://github.com/rtc-io/rtc-testbot.git /srv/testbot
  +WORKDIR /srv/testbot
  +RUN npm install
  
positive.code: # install packages
  RUN apt-get install -y nodejs git xvfb build-essential git
  
  # configure video loopback
  RUN /tmp/setup-loopbackvideo.sh
  
  # create the testbot user
  RUN useradd -p testbot testbot
  
negative.code: FROM ubuntu:14.04
  MAINTAINER Damon Oehlman <damon.oehlman@nicta.com.au>
  
  # configure environment
  ENV DISPLAY :99.0
  ENV CHROME_DEB google-chrome-stable_current_amd64.deb
  
  # use aarnet mirror for quicker building while developing
  RUN sed -i 's/archive.ubuntu.com/mirror.aarnet.edu.au\/pub\/ubuntu\/archive/g' /etc/apt/sources.list
  