anchor.diff:   && sed -ri "s/(security).debian.org/${APT_MIRROR:-security.debian.org}/g" /etc/apt/sources.list
   
   FROM base AS criu
  +ARG DEBIAN_FRONTEND
   # Install CRIU for checkpoint/restore support
   ENV CRIU_VERSION 3.11
   # Install dependency packages specific to criu
  
positive.code: 
  ARG CROSS="false"
  ARG GO_VERSION=1.12.7
  
  FROM golang:${GO_VERSION}-stretch AS base
  ARG APT_MIRROR
  
negative.code: FROM cross-${CROSS} as dev-base
  
  FROM dev-base AS runtime-dev-cross-false
  ARG DEBIAN_FRONTEND
  RUN apt-get update && apt-get install -y --no-install-recommends \
  	libapparmor-dev \
  	libseccomp-dev \
  	&& rm -rf /var/lib/apt/lists/*
  FROM cross-true AS runtime-dev-cross-true
  ARG DEBIAN_FRONTEND
  # These crossbuild packages rely on gcc-<arch>, but this doesn't want to install
  # on non-amd64 systems.
  # Additionally, the crossbuild-amd64 is currently only on debian:buster, so
  