anchor.diff:    ihaskellExe = nixpkgs.haskell.lib.justStaticExecutables haskellPackages.ihaskell;
     ihaskellEnv = haskellPackages.ghcWithPackages packages;
     jupyterlab = nixpkgs.python3.withPackages (ps: [ ps.jupyterlab ] ++ pythonPackages ps);
  -
     ihaskellGhcLibFunc = exe: env: nixpkgs.writeShellScriptBin "ihaskell" ''
       ${exe}/bin/ihaskell -l $(${env}/bin/ghc --print-libdir) "$@"
     '';
  -  ihaskellGhcLib = ihaskellGhcLibFunc ihaskellExe ihaskellEnv;
  -
     ihaskellKernelFileFunc = ihaskellGhcLib: rtsopts: {
       display_name = "Haskell";
       argv = [
  
positive.code:         fi
        done
      '';
  
      passthru = {
        inherit haskellPackages;
        inherit ihaskellExe;
  
negative.code:     ];
      language = "haskell";
    };
    ihaskellKernelSpecFunc = ihaskellKernelFile: nixpkgs.runCommand "ihaskell-kernel" {} ''
      export kerneldir=$out/kernels/haskell
      mkdir -p $kerneldir
      cp ${./html}/* $kerneldir
      echo '${builtins.toJSON ihaskellKernelFile}' > $kerneldir/kernel.json
    '';
    ihaskellLabextension = nixpkgs.runCommand "ihaskell-labextension" {} ''
      mkdir -p $out/labextensions/
      ln -s ${./jupyterlab-ihaskell/labextension} $out/labextensions/jupyterlab-ihaskell
    '';
    ihaskellDataDirFunc = ihaskellKernelSpec: ihaskellLabextension: nixpkgs.buildEnv {
      name = "ihaskell-data-dir";
      paths = [ ihaskellKernelSpec ihaskellLabextension ];
    };
    ihaskellBuildEnvFunc = { ihaskellEnv, jupyterlab, systemPackages, ihaskellDataDir }: nixpkgs.buildEnv {
      name = "ihaskell-with-packages";
      buildInputs = [ nixpkgs.makeWrapper ];
  