anchor.diff:        pcg_c
   
         # Database
  +      mysql
         postgresql
  -
  -      # Ops
  -      ansible2
   
         # analysis
         gnuplot
  
positive.code:     ignoreCollisions = true;
      paths = [
        abcde
        bitcoin
        cdparanoia
        gitAndTools.git-annex
        pidgin
        fontforge
      ];
  
negative.code:       unzip
        lzma
        unrar
        zip
  
        # filesystem
        fuse
  