anchor.diff:        ghc
   
         # Misc userland packages.
  +      auca
         hledger
  +      hlint
  +      shellcheck
  +      stack
  +      pandoc
  +      gitAndTools.git-annex
       ];
     });
   
  
positive.code:       emacs
        xsel
        vim
        silver-searcher
        colordiff
        gnupg
        openssl
  
negative.code:       pcg_c
  
        # Database
        mysql
        postgresql
  
        # analysis
        gnuplot
  