anchor.diff:        ];
       };
   
  +    # personal utilities
       phocid  = haskellPackages.callPackage ~/proj/phocid {};
  -    pinfold = haskellPackages.callPackage ~/work/pinfold {};
  -    ybapp   = haskellPackages.callPackage ~/work/ybapp {};
   
  +    # haskell environment
       myHaskellEnv = haskellPackages.ghcWithHoogle (p: with p; [
         cabal-install
         ghc-mod
  
positive.code: {
    allowUnfree = true;
  
    # define a environment i can install/update with
    #
    # $ nix-env -iA nixpkgs.all
    packageOverrides = super: let self = super.pkgs; in with self; rec {
  
      all = buildEnv {
        name = "all";
        paths = [
          phocid
          pinfold
          ybapp
  
          myHaskellEnv
          cabal2nix
  
negative.code:       regex-tdfa
        shakespeare
        snap
        snap-core
        snap-loader-dynamic
        snap-loader-static
        snap-server
        snaplet-postgresql-simple
        snaplet-sass
        text
        time
        transformers
        vector
        xlsx
      ]);
  