anchor.diff:  RUN DEBIAN_FRONTEND=noninteractive R CMD INSTALL \
       clipr_0.4.1.tar.gz \
       ps_1.1.0.tar.gz \
  -    processx_3.2.0.tar.gz \
       modelr_0.1.2.tar.gz \
       reprex_0.2.0.tar.gz \
       tidyverse_1.2.1.tar.gz \
  
positive.code:    bitops_1.0-6.tar.gz \
     RCurl_1.95-4.12.tar.gz \
     plyr_1.8.4.tar.gz \
     R6_2.4.0.tar.gz \
     curl_3.3.tar.gz \
     sys_3.1.tar.gz \
     askpass_1.1.tar.gz \
  
negative.code: 
  # R packages we need for devtools - and we need devtools to be able to update the rmarkdown package
  RUN DEBIAN_FRONTEND=noninteractive wget \
     https://archive.linux.duke.edu/cran/src/contrib/processx_3.3.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/callr_3.2.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/cli_1.1.0.tar.gz \
     https://archive.linux.duke.edu/cran/src/contrib/pkgbuild_1.0.2.tar.gz \
  