anchor.diff:  
   RUN apt-get update && apt-get install -y --no-install-recommends \
     ca-certificates \
  +  build-essential \
     wget \
     g++ \
     git \
  
positive.code:   --with-system \
    --with-thread
  
  RUN wget http://downloads.sourceforge.net/project/boost/boost/${boost_version}/${boost_dir}.tar.gz \
    && echo "${boost_sha256_sum}  ${boost_dir}.tar.gz" | sha256sum -c \
    && tar xfz ${boost_dir}.tar.gz \
  
negative.code: 
  WORKDIR /tmp
  
  # set boost envs
  ARG boost_version=1.62.0
  ARG boost_dir=boost_1_62_0
  ARG boost_sha256_sum=440a59f8bc4023dbe6285c9998b0f7fa288468b889746b1ef00e8b36c559dce1
  