anchor.diff:      rust-$RUST_VERSION-x86_64-unknown-linux-gnu.tar.gz \
       /var/lib/apt/lists/* \
       /tmp/* \
  -    /var/tmp/* && \
  -  cargo install rustfmt
  +    /var/tmp/*
   
   # add jenkins user
   RUN useradd jenkins --shell /bin/bash --create-home
  
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:     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 \
  