anchor.diff:  
   # pre-build btrfs-progs
   RUN apt-get update && \
  -      apt-get -y install liblzo2-dev libblkid-dev e2fslibs-dev pkg-config libz-dev && \
  +      apt-get -y install liblzo2-dev libblkid-dev e2fslibs-dev libz-dev && \
         cd /tmp && \
         curl https://www.kernel.org/pub/linux/kernel/people/kdave/btrfs-progs/btrfs-progs-v4.4.tar.gz | tar zxf - && \
         cd btrfs-progs-v4.4 && \
  
positive.code:       cp btrfs mkfs.btrfs /opt/static-assets && \
        cd /tmp && \
        rm -rf btrfs-progs-v4.4 && \
        apt-get -y remove liblzo2-dev libblkid-dev e2fslibs-dev pkg-config libz-dev
  
  # pre-build libseccomp
  RUN cd /tmp && \
        curl https://github.com/seccomp/libseccomp/releases/download/v2.3.1/libseccomp-2.3.1.tar.gz | tar zxf - &&
        cd libseccomp-2.3.1 && \
        ./configure --prefix=/opt/static-assets/libseccomp && \
        make && \
        make install && \
        cd /tmp && \
        rm -rf libseccomp-2.3.1
  
negative.code:       cd .. && \
        rm -rf tar-1.28
  
  # install pkg-config for building btrfs-progs and runc with seccomp
  RUN apt-get update && \
        apt-get -y install pkg-config
  
  # pre-build `iptables`
  RUN apt-get update && \
        apt-get -y install bzip2 && \
  