anchor.diff:  rec {
   
  -  # Content-addressable Nix mirrors.
  +  # Content-addressable Nix mirrors
     hashedMirrors = [
       http://tarballs.nixos.org
     ];
  
positive.code: 
    # OpenBSD mirrors
    openbsd = [
      http://ftp.openbsd.org/pub/OpenBSD/
      ftp://ftp.nluug.nl/pub/OpenBSD/
      ftp://ftp-stud.fht-esslingen.de/pub/OpenBSD/
      ftp://ftp.halifax.rwth-aachen.de/pub/OpenBSD/
      ftp://mirror.switch.ch/pub/OpenBSD/
    ];
  }
  
negative.code:     http://kent.dl.sourceforge.net/sourceforge/
    ];
  
    # SourceForge.jp
    sourceforgejp = [
      http://osdn.dl.sourceforge.jp/
      http://jaist.dl.sourceforge.jp/
  