anchor.diff:      globals_0.12.2.tar.gz \
       iterators_1.0.10.tar.gz \
       listenv_0.7.0.tar.gz \
  -    processx_3.2.0.tar.gz \
       clipr_0.4.1.tar.gz \
       tidyverse_1.2.1.tar.gz \
       promises_1.0.1.tar.gz \
  
positive.code: 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 \
  
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 \
  