add TU Dresden corporate design LaTeX classes

shell.nix

@@ -1,4 +1,8 @@
 with import <nixpkgs> {};
+let
+  tud-cd = callPackage ./tud-cd-latex.nix {};
+
+in
 mkShell {
   buildInputs = [
     gnumake
@@ -23,9 +27,16 @@ mkShell {
       ccicons
       biblatex
       logreq
-      koma-script;
+      koma-script
+      ;
+
+      # custom LaTeX class, see https://github.com/NixOS/nixpkgs/issues/11893#issuecomment-166834399
+      "tud-cd" = {
+        pkgs = [ tud-cd ];
+      };
     })
     biber
+    tud-cd
 
     # for instance DNS query script
     (python3.withPackages (ps: with ps; [ 

tud-cd-latex.nix

@@ -0,0 +1,18 @@
+{ stdenv, fetchFromGitHub }:
+
+stdenv.mkDerivation rec {
+  name = "tud-cd";
+  src = fetchFromGitHub {
+    owner = "tud-cd";
+    repo = name;
+    rev = "ff22134151d5e0afcfb3a0a583b4bff752d03a82";
+    sha256 = "0qagiwm6d028nxis6ca3dfjy6hicbn3w154l15h8rnasnkbzybqi";
+  };
+  phases = [ "unpackPhase" "installPhase" ];
+  installPhase = ''
+    cp -r ./ $out
+  '';
+  # required for texlive.combine
+  pname = name;
+  tlType = "run";
+}