diff --git a/overlay/default.nix b/overlay/default.nix
index a4bb72a..667c692 100644
--- a/overlay/default.nix
+++ b/overlay/default.nix
@@ -3,43 +3,44 @@ final: prev:
 with prev;
 
 let
-  overrideHost = drv: attrs:
+  # Helper functions to override package dependant
+  # on whether the host or target system is Genode.
+
+  overrideHost = attrs: drv:
     if hostPlatform.isGenode then drv.override attrs else drv;
 
-  overrideHostAttrs = drv: f:
+  overrideTarget = attrs: drv:
+    if targetPlatform.isGenode then drv.override attrs else drv;
+
+  overrideAttrsHost = f: drv:
     if hostPlatform.isGenode then drv.overrideAttrs f else drv;
 
-  overrideTarget = drv: f:
-    if targetPlatform.isGenode then drv.override f else drv;
-
-  overrideTargetAttrs = drv: f:
+  overrideAttrsTarget = f: drv:
     if targetPlatform.isGenode then drv.overrideAttrs f else drv;
 
-  addPatches = drv: patch:
-    overrideTargetAttrs drv
-    (attrs: { patches = attrs.patches or [ ] ++ [ patch ]; });
+  addPatches' = patches: attrs: { patches = attrs.patches or [ ] ++ patches; };
 
-  addHostPatches = if hostPlatform.isGenode then
-    drv: patches:
-    overrideTargetAttrs drv
-    (attrs: { patches = attrs.patches or [ ] ++ patches; })
-  else
-    drv: _: drv;
+  addPatchesHost = ps: overrideAttrsHost (addPatches' ps);
+
+  addPatchesTarget = ps: overrideAttrsTarget (addPatches' ps);
+
+  autoreconfHost = overrideAttrsHost
+    (attrs: { nativeBuildInputs = [ final.autoreconfHook ]; });
 
 in {
 
-  bash = overrideTargetAttrs bash (attrs: {
+  bash = overrideAttrsTarget (attrs: {
     configureFlags = attrs.configureFlags
       ++ [ "--without-bash-malloc" ]; # no sbrk please
     postPatch = "sed '/check_dev_tty/d' shell.c";
-  });
+  }) bash;
 
-  binutils-unwrapped = overrideTargetAttrs binutils-unwrapped (attrs: {
+  binutils-unwrapped = overrideAttrsTarget (attrs: {
     patches = attrs.patches ++ [ ./binutils/support-genode.patch ];
     nativeBuildInputs = [ final.updateAutotoolsGnuConfigScriptsHook ];
-  });
+  }) binutils-unwrapped;
 
-  cmake = overrideTargetAttrs cmake (attrs: {
+  cmake = overrideAttrsTarget (attrs: {
     postInstall = with stdenv; ''
       local MODULE="$out/share/cmake-${
         lib.versions.majorMinor attrs.version
@@ -50,27 +51,24 @@ in {
       fi
       cp ${./cmake/Genode.cmake} $MODULE
     '';
-  });
+  }) cmake;
 
-  coreutils = if targetPlatform.isGenode then
-    (coreutils.override {
-      gmp = null;
-      libiconv = null;
-    }).overrideAttrs (attrs: {
-      configureFlags = [
-        "--disable-acl"
-        "--disable-largefile"
-        "--disable-xattr"
-        "--disable-libcap"
-        "--disable-nls"
-      ];
-      LDFLAGS = [ "-Wl,--no-as-needed" ];
-      # keep libposix NEEDED
-    })
-  else
-    coreutils;
+  coreutils = overrideHost {
+    gmp = null;
+    libiconv = null;
+  } (overrideAttrsHost (attrs: {
+    configureFlags = [
+      "--disable-acl"
+      "--disable-largefile"
+      "--disable-xattr"
+      "--disable-libcap"
+      "--disable-nls"
+    ];
+    LDFLAGS = [ "-Wl,--no-as-needed" ];
+    # keep libposix NEEDED
+  }) coreutils);
 
-  gdb = addPatches gdb [ ./gdb/genode.patch ];
+  gdb = addPatchesTarget [ ./gdb/genode.patch ] gdb;
 
   genodeLibcCross = callPackage ./libc { };
 
@@ -78,9 +76,9 @@ in {
     inherit flake;
     pkgs = final;
   };
-
-  libconfig = overrideHostAttrs libconfig
-    (attrs: { configureFlags = [ "--disable-examples" ]; });
+  libconfig =
+    overrideAttrsHost (attrs: { configureFlags = [ "--disable-examples" ]; })
+    libconfig;
 
   libcCrossChooser = name:
     if stdenv.targetPlatform.isGenode then
@@ -88,20 +86,22 @@ in {
     else
       prev.libcCrossChooser name;
 
-  libsodium = overrideHostAttrs libsodium (attrs: {
+  libsodium = overrideAttrsHost (attrs: {
     patches = (attrs.patches or [ ]) ++ [ ./libsodium/genode.patch ];
-  });
+  }) libsodium;
 
-  libtool = overrideTargetAttrs libtool (attrs: {
-    nativeBuildInputs = attrs.nativeBuildInputs ++ [ autoconf automake115x ];
+  libkrb5 = autoreconfHost libkrb5;
+
+  libtool = overrideAttrsTarget (attrs: {
+    nativeBuildInputs = with final;
+      attrs.nativeBuildInputs ++ [ autoconf automake115x ];
     patches = ./libtool/genode.patch;
-  });
+  }) libtool;
 
-  libtoxcore = overrideHost libtoxcore {
+  libtoxcore = overrideHost {
     libopus = null;
     libvpx = null;
-    ncurses = null;
-  };
+  } libtoxcore;
 
   llvmPackages_11 = callPackage ./llvm-11 ({
     inherit (stdenvAdapters) overrideCC;
@@ -113,9 +113,9 @@ in {
       stdenv = gcc7Stdenv;
     });
 
-  ncurses = addHostPatches ncurses [ ./ncurses/genode.patch ];
+  ncurses = addPatchesHost [ ./ncurses/genode.patch ] ncurses;
 
-  openssl = overrideHostAttrs openssl (attrs: {
+  openssl = overrideAttrsHost (attrs: {
     outputs = [ "out" ]
       ++ builtins.filter (x: x != "bin" && x != "out") attrs.outputs;
     patches = attrs.patches or [ ] ++ [ ./openssl/genode.patch ];
@@ -126,21 +126,22 @@ in {
     configureFlags = attrs.configureFlags ++ [ "no-devcryptoeng" ];
     postInstall =
       "rm $out/bin/c_rehash"; # eliminate the perl runtime dependency
-  });
+  }) openssl;
 
-  rsync = overrideHostAttrs (overrideHost rsync {
+  rsync = overrideHost {
     enableACLs = false;
     popt = null;
-  }) (attrs: { outputs = [ "out" "man" ]; });
+  } (overrideAttrsHost (attrs: { outputs = [ "out" "man" ]; }) rsync);
 
   solo5-tools = callPackage ./solo5-tools { };
 
-  zlib = overrideHostAttrs zlib (attrs: {
+  zlib = overrideAttrsHost (attrs: {
     postInstall = attrs.postInstall or "" + ''
       pushd ''${!outputLib}/lib
       find . -type l -delete
       mv libz.so.* libz.so
       popd
     '';
-  });
+  }) zlib;
+
 }