anchor.diff:      git \
       libssl-dev \
       pkg-config && \
  +  # install rust binaries
     curl -sO https://static.rust-lang.org/dist/rust-$RUST_VERSION-x86_64-unknown-linux-gnu.tar.gz && \
     tar -xzf rust-$RUST_VERSION-x86_64-unknown-linux-gnu.tar.gz && \
     ./rust-$RUST_VERSION-x86_64-unknown-linux-gnu/install.sh --without=rust-docs && \
  +  # install nodejs
     curl -sL https://deb.nodesource.com/setup_7.x | bash - && \
     apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y nodejs && \
  +  # install rustfmt
  +  cargo install rustfmt && \
  +  mv /root/.cargo/bin/rustfmt /usr/local/bin && \
  +  # cleanup
     DEBIAN_FRONTEND=noninteractive apt-get remove --purge -y curl && \
     DEBIAN_FRONTEND=noninteractive apt-get autoremove -y && \
     rm -rf \
  
positive.code: ENV USER root
  ENV RUST_VERSION=1.16.0
  
  # install git, rust, cargo, npm
  RUN apt-get update && \
    DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
      build-essential \
  
negative.code:     rust-$RUST_VERSION-x86_64-unknown-linux-gnu.tar.gz \
      /var/lib/apt/lists/* \
      /tmp/* \
      /var/tmp/*
  
  # add jenkins user
  RUN useradd jenkins --shell /bin/bash --create-home
  