anchor.diff:     https://archive.linux.duke.edu/cran/src/contrib/processx_3.3.0.tar.gz \
      https://archive.linux.duke.edu/cran/src/contrib/ps_1.3.0.tar.gz \
      https://archive.linux.duke.edu/cran/src/contrib/callr_3.2.0.tar.gz \
  +   https://archive.linux.duke.edu/cran/src/contrib/crayon_1.3.4.tar.gz \
  +   https://archive.linux.duke.edu/cran/src/contrib/assertthat_0.2.0.tar.gz \
      https://archive.linux.duke.edu/cran/src/contrib/cli_1.1.0.tar.gz \
      https://archive.linux.duke.edu/cran/src/contrib/pkgbuild_1.0.2.tar.gz \
      https://archive.linux.duke.edu/cran/src/contrib/pkgload_1.0.2.tar.gz \
  
positive.code:    scales_1.0.0.tar.gz \
     proto_1.0.0.tar.gz \
     reshape2_1.4.3.tar.gz \
     assertthat_0.2.0.tar.gz \
     lazyeval_0.2.1.tar.gz \
     rlang_0.2.2.tar.gz \
     utf8_1.1.4.tar.gz \
     crayon_1.3.4.tar.gz \
     fansi_0.3.0.tar.gz \
     pillar_1.3.0.tar.gz \
     tibble_1.4.2.tar.gz \
  
negative.code: # libraries Eric Green wanted
  RUN DEBIAN_FRONTEND=noninteractive wget \
     https://archive.linux.duke.edu/cran/src/contrib/lubridate_1.7.4.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/lazyeval_0.2.1.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/rlang_0.2.2.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/utf8_1.1.4.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/fansi_0.3.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/pillar_1.3.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/tibble_1.4.2.tar.gz \
  