anchor.diff:  
   # programs needed for building
   RUN apt-get update && apt-get install -y \
  -  build-essential \
  -  curl \
  -  sudo \
  -  unzip \
  -  wget \
  -  gnupg2 \
  -  apt-utils \
  -  software-properties-common \
  -  bzr
  +    build-essential \
  +    curl \
  +    sudo \
  +    unzip \
  +    wget \
  +    gnupg2 \
  +    apt-utils \
  +    software-properties-common \
  +    bzr
   
   RUN add-apt-repository ppa:git-core/ppa && apt-get update && apt-get install -y git
   
  
positive.code: 
  # install yarn
  RUN curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add - && \
    echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list && \
    apt-get update && \
    apt-get install yarn
  
  # install bower
  RUN npm install -g bower && \
      echo '{ "allow_root": true }' > /root/.bowerrc
  
  # install jdk 12
  RUN curl -L -o openjdk12.tar.gz https://download.java.net/java/GA/jdk12.0.2/e482c34c86bd4bf8b56c0b35558996b9/10/GPL/openjdk-12.0.2_linux-x64_bin.tar.gz && \
  
negative.code: # install NuGet (w. mono)
  # https://docs.microsoft.com/en-us/nuget/install-nuget-client-tools#macoslinux
  RUN apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF &&\
      echo "deb https://download.mono-project.com/repo/ubuntu stable-bionic main" | sudo tee /etc/apt/sources.list.d/mono-official-stable.list &&\
      apt-get update &&\
      apt-get install -y mono-complete &&\
      curl -o "/usr/local/bin/nuget.exe" "https://dist.nuget.org/win-x86-commandline/latest/nuget.exe" &&\
      curl -o "/usr/local/bin/nugetv3.5.0.exe" "https://dist.nuget.org/win-x86-commandline/v3.5.0/nuget.exe"
  
  # install dotnet core
  RUN wget -q https://packages.microsoft.com/config/ubuntu/18.04/packages-microsoft-prod.deb &&\
      sudo dpkg -i packages-microsoft-prod.deb &&\
      rm packages-microsoft-prod.deb &&\
      sudo apt-get update &&\
      sudo apt-get install -y dotnet-runtime-2.1 dotnet-sdk-2.1 dotnet-sdk-2.2 dotnet-sdk-3.0 dotnet-sdk-3.1
  
  # install Composer
  # The ARG and ENV are for installing tzdata which is part of this installaion.
  