configuration.nix

let
  tudscr.pkgs = [(pkgs.callPackage (import ./tudscr.nix) {})];
  mytexlive = (pkgs.texlive.combine {                                                                                                                                                          
     inherit (pkgs.texlive)                                                                                                                                                                    
     scheme-basic                                                                                                                                                                              
     collection-bibtexextra                                                                                                                                                                    
     collection-binextra                                                                                                                                                                       
     collection-fontsrecommended                                                                                                                                                               
     collection-genericextra                                                                                                                                                                   
     collection-genericrecommended                                                                                                                                                             
     collection-latex                                                                                                                                                                          
     collection-latexextra                                                                                                                                                                     
     collection-latexrecommended                                                                                                                                                               
     collection-science                                                                                                                                                                        
     collection-xetex;
     inherit tudscr;
  });
in rec {
  # ...
  environment.systemPackages = [mytexlive];
}
  

tudscr.nix

{stdenv, fetchurl, unzip}:
stdenv.mkDerivation rec {                                                                                                                                                                      
  version = "2.03a";                                                                                                                                                                           
  pname = "tudscr";                                                                                                                                                                            
  name = "${pname}-${version}";                                                                                                                                                                
  tlType = "run";                                                                                                                                                                              
                                                                                                                                                                                               
  src = fetchurl {                                                                                                                                                                             
    url = "https://github.com/tud-cd/tudscr/releases/download/v${version}/tudscr_v${version}.zip";                                                                                             
    sha256 = "0cpz5chnqznh2bs5ni4m0fd0c38n99yh6wvdg8nxd80jk5hyh1zz";                                                                                                                           
  };                                                                                                                                                                                           
                                                                                                                                                                                               
  buildInputs = [ unzip ];                                                                                                                                                                     
                                                                                                                                                                                               
  # Multiple files problem                                                                                                                                                                     
  unpackPhase = ''                                                                                                                                                                             
  mkdir tudscr                                                                                                                                                                                 
  cd tudscr                                                                                                                                                                                    
  unzip $src                                                                                                                                                                                   
  '';                                                                                                                                                                                          
                                                                                                                                                                                               
  dontBuild = true;                                                                                                                                                                            
                                                                                                                                                                                               
  installPhase = "                                                                                                                                                                             
  mkdir -p $out                                                                                                                                                                                
  cp -prd doc tex $out                                                                                                                                                                         
  ";                                                                                                                                                                                           
                                                                                                                                                                                               
  meta = {                                                                                                                                                                                     
    branch = "3";                                                                                                                                                                              
    platforms = stdenv.lib.platforms.unix;                                                                                                                                                     
  };                                                                                                                                                                                           
}