anchor.diff: -FROM ubuntu:16.04
  +FROM ubuntu:16.04 as toolchain
   
   # `build-essential` and `file` are needed for backtrace-sys
   # `cmake`, `git`, `python` are needed for wasm tools
  
positive.code: RUN cargo build --release
  RUN rm src/*.rs
  
  ADD crate-information.json /playground/crate-information.json
  
  ADD postinstall.sh /root/
  RUN /root/postinstall.sh ${channel}
  ADD cargo-wasm /root/.cargo/bin/
  
negative.code: 
  RUN curl https://sh.rustup.rs -sSf | sh -s -- -y --default-toolchain "${channel}"
  
  # Prebuild the playground's dependencies
  
  FROM toolchain as dependencies
  
  RUN cd / && \
      cargo new playground
  WORKDIR /playground
  