diff --git a/packages/genodelabs/default.nix b/packages/genodelabs/default.nix
index 0348c2f..fdfe6d3 100644
--- a/packages/genodelabs/default.nix
+++ b/packages/genodelabs/default.nix
@@ -123,6 +123,63 @@ let
   ports =
     lib.mapAttrs preparePort (import ./ports.nix { inherit buildPackages; });
 
+  toolchain' = buildPackages.stdenv.mkDerivation rec {
+    pname = "toolchain";
+    version = "19.05";
+    # use the sources of the last toolchain update
+    src = fetchurl {
+      url = "https://github.com/genodelabs/genode/archive/${version}.tar.gz";
+      hash = "sha256-nK+smAvxbbcQQ3gY7BmFvnQ6MjNbbUfvcU5qXxAKKNc=";
+    };
+
+    nativeBuildInputs = with buildPackages; [
+      autoconf264
+      autogen
+      expat
+      expect
+      gnupg
+      ncurses
+      pkg-config
+      texinfo
+      tcl
+      wget
+      which
+    ];
+
+    portInputs = with ports; [ gmp mpfr mpc gcc binutils gdb ];
+
+    patches = [ ./toolchain-ada.patch ];
+
+    configurePhase = let
+      linkPorts = toString
+        (builtins.map (drv: " ln -sv ${drv}/* $CONTRIB_DIR/;") portInputs);
+    in ''
+      runHook preConfigure
+      export GENODE_DIR="$(pwd)"
+      export CONTRIB_DIR=$GENODE_DIR/contrib
+      export BUILD_DIR=$GENODE_DIR/build
+      echo true > tool/ports/prepare_port
+      patchShebangs tool
+      mkdir $CONTRIB_DIR; ${linkPorts}
+      runHook postConfigure
+    '';
+
+    makefile = "tool/tool_chain";
+    buildFlags = let
+      arch = with platform;
+        if isx86 then
+          "x86"
+        else if isAarch32 then
+          "arm"
+        else if isAarch64 then
+          "aarch64"
+        else
+          throw "unknown toolchain for platform ${platform.system}";
+    in [ "INSTALL_LOCATION=$out" "VERBOSE=" arch ];
+
+    dontInstall = true;
+  };
+
   toolchain = callPackage ./toolchain.nix { };
 
   stdenv' =
@@ -281,7 +338,7 @@ let
     };
 
 in genodeSources // {
-  inherit buildUpstream buildDepot ports specs toolchain genodeBase;
+  inherit buildUpstream buildDepot ports specs toolchain genodeBase toolchain';
 
   make = target:
     let
diff --git a/packages/genodelabs/gcc-port.patch b/packages/genodelabs/gcc-port.patch
new file mode 100644
index 0000000..69ee4dc
--- /dev/null
+++ b/packages/genodelabs/gcc-port.patch
@@ -0,0 +1,22 @@
+commit 30d76a7231701e20e82ee025a36541e3bbc7276a
+Author: Emery Hemingway <ehmry@posteo.net>
+Date:   Sat Aug 15 17:19:10 2020 +0200
+
+    gcc.port: remove check_tool tests
+
+diff --git a/repos/ports/ports/gcc.port b/repos/ports/ports/gcc.port
+index 5a6c6bb683..39fecd2fee 100644
+--- a/repos/ports/ports/gcc.port
++++ b/repos/ports/ports/gcc.port
+@@ -14,11 +14,6 @@ PATCH_OPT := -p1 -d ${DIR(gcc)}
+ 
+ HASH_INPUT += $(REP_DIR)/${DIR(gcc)}/patches/series
+ 
+-AUTOCONF := autoconf2.64
+-
+-$(call check_tool,$(AUTOCONF))
+-$(call check_tool,autogen)
+-
+ default: _patch
+ 	@#
+ 	@# Re-generate configure scripts
diff --git a/packages/genodelabs/toolchain-ada.patch b/packages/genodelabs/toolchain-ada.patch
new file mode 100644
index 0000000..2e23c79
--- /dev/null
+++ b/packages/genodelabs/toolchain-ada.patch
@@ -0,0 +1,37 @@
+commit 1b6e706b705e48dd2741c8263b8df953b1863260
+Author: Emery Hemingway <ehmry@posteo.net>
+Date:   Sat Aug 15 16:34:16 2020 +0200
+
+    toolchain: remove ada support
+    
+    Gnat and gprbuild not conveniently available for aarch64.
+
+diff --git a/tool/tool_chain b/tool/tool_chain
+index 038147e7d6..4e94d210df 100755
+--- a/tool/tool_chain
++++ b/tool/tool_chain
+@@ -172,8 +172,7 @@ GPRBUILD_OK = $(call check_nonempty_f,$(shell which gprbuild),\
+                 Need to have 'gprbuild' installed.)
+ 
+ TOOLS_OK = $(AUTOCONF_OK) $(AUTOCONFINST_OK) $(PKG_CONFIG_OK) $(CURSES_OK) \
+-           $(TEXINFO_OK) $(WGET_OK) $(AUTOGEN_OK) $(GPG_OK) $(EXPAT_OK) \
+-           $(GNAT_OK) $(GPRBUILD_OK)
++           $(TEXINFO_OK) $(WGET_OK) $(AUTOGEN_OK) $(GPG_OK) $(EXPAT_OK)
+ 
+ ifneq ($(strip $(TOOLS_OK)),)
+ $(error Please install missing tools.)
+@@ -221,12 +220,12 @@ LANGUAGES              = c,c++
+ LIB_GCC                = cd $(INSTALL_LOCATION)/lib/gcc/riscv64-unknown-elf/$(GCC_VERSION)/rv64imac/lp64 && \
+                          $(SUDO) ln -sf ../../include include
+ else
+-LANGUAGES              = c,c++,ada
++LANGUAGES              = c,c++
+ LIB_GCC                =
+ endif
+ 
+ GCC_BOOTSTRAP_CONFIG += $(COMMON_BOOTSTRAP_CONFIG) \
+-                        --enable-languages=c,c++,ada \
++                        --enable-languages=c,c++ \
+                         --disable-bootstrap \
+                         --disable-libatomic \
+                         --disable-libcilkrts \