diff --git a/pkgs/apps/dalton/default.nix b/pkgs/apps/dalton/default.nix
index 8ac02d15..be73fbfa 100644
--- a/pkgs/apps/dalton/default.nix
+++ b/pkgs/apps/dalton/default.nix
@@ -1,13 +1,48 @@
-
-{ stdenv, lib, fetchgit, gfortran, cmake, makeWrapper
-, which, openssh, blas, lapack, mpi, python3
-} :
+{ stdenv
+, lib
+, fetchurl
+, fetchFromGitHub
+, fetchFromGitLab
+, gfortran
+, cmake
+, makeWrapper
+, which
+, openssh
+, blas
+, lapack
+, mpi
+, python3
+}:
 
 assert
-  lib.asserts.assertMsg
+lib.asserts.assertMsg
   (!blas.isILP64)
   "A 32 bit integer implementation of BLAS is required.";
 
+let
+  gen1intSrc = fetchFromGitLab {
+    owner = "bingao";
+    repo = "gen1int";
+    rev = "1e4148ecd676761b3399801acba443925a1fee6b";
+    hash = "sha256-kauwbL95TII3AVCs3H3oiy5DECqwh5JEuF/UhlBEnEE=";
+  };
+
+  pelibSrc = fetchFromGitLab {
+    owner = "pe-software";
+    repo = "pelib";
+    rev = "19dd0e91afbd18b7c9f2611b9978b1aeaa1c19f9";
+    hash = "sha256-sFgolAju05svkqozjAb2D5V0S48b9dHDOPRWD8F9fPs=";
+  };
+
+  qfitlibSrc = fetchFromGitHub {
+    owner = "cstein";
+    repo = "qfitlib";
+    rev = "1acdc9863fdeae2cdbc7f5a599413257a095b8ad";
+    hash = "sha256-GnGyWpNMrxsD9GNqGpzntDIpveDn3y4fG3m2zJbThwc=";
+  };
+
+
+in
 stdenv.mkDerivation rec {
   pname = "dalton";
   version = "2020.1";
@@ -29,23 +64,28 @@ stdenv.mkDerivation rec {
     which
   ];
 
-  # Many submodules are required and they are not fetched by fetchFromGitLab.
-  src = fetchgit  {
-    url = "https://gitlab.com/dalton/dalton.git";
-    rev = "9d7c5e435b75a9695d5ac8714121d12e6486149f"; # Git hash of 2020.1 as of 15.02.2022.
-    sha256 = "sha256-WTKouo+JfeZf1w5kflMO8X5uhgHnsO/3RXi44QzIdHk=";
-    deepClone = true;
+  src = fetchurl {
+    url = "https://gitlab.com/dalton/${pname}/-/archive/${version}/dalton-${version}.tar.bz2";
+    hash = "sha256-Rn1BZsJrQ0jYBUoQQafDpbpz19wc2LHWof5N6ZlKE1U=";
   };
 
-  postPatch = "patchShebangs .";
+  postPatch = ''
+    cp -r ${gen1intSrc}/* external/gen1int/.
+    cp -r ${pelibSrc}/* external/pelib/.
+    cp -r ${qfitlibSrc}/* external/qfitlib/.
+
+    chmod -R +rwx external/*
+
+    patchShebangs .
+  '';
 
   FC = "mpif90";
   CC = "mpicc";
   CXX = "mpicxx";
 
   /*
-  Cmake is required to build but adding it to the buildinputs then ignores the setup script.
-  Therefore i call the script here manually but cmake is invoked by setup.
+    Cmake is required to build but adding it to the buildinputs then ignores the setup script.
+    Therefore i call the script here manually but cmake is invoked by setup.
   */
   configurePhase = ''
     ./setup --prefix=$out --mpi && cd build
@@ -56,8 +96,8 @@ stdenv.mkDerivation rec {
   hardeningDisable = [ "format" ];
 
   /*
-  Dalton does not care about bin lib share directory structures and puts everything in a single
-  directory. Clean up the mess here.
+    Dalton does not care about bin lib share directory structures and puts everything in a single
+    directory. Clean up the mess here.
   */
   postInstall = ''
     mkdir -p $out/bin $out/share/dalton
@@ -76,7 +116,7 @@ stdenv.mkDerivation rec {
   '';
 
   /*
-  Make the MPI stuff available to the Dalton script. Direct exposure of MPI is not necessary.
+    Make the MPI stuff available to the Dalton script. Direct exposure of MPI is not necessary.
   */
   postFixup = ''
     wrapProgram $out/bin/dalton \