diff --git a/flake.nix b/flake.nix
index 3b5cdce..fbdbf78 100644
--- a/flake.nix
+++ b/flake.nix
@@ -20,13 +20,16 @@
             });
           
           # robossembler custom packages; defined here for share between devShells and packages
-          bpy = pkgs.python3Packages.callPackage ./pkgs/development/python-modules/bpy { };
           blender = pkgs.callPackage ./pkgs/misc/blender { };
+          bpy = pkgs.python3Packages.callPackage ./pkgs/development/python-modules/bpy { };
+          pysdf = pkgs.python3Packages.callPackage ./pkgs/development/python-modules/pysdf { };
         in
         {
           packages = {
             blender = blender;
-            python3Packages = pkgs.recurseIntoAttrs bpy;
+            bpy = bpy;
+            pysdf = pysdf;
+            gazebo = ros.humble.gazebo;
           };
 
           devShells.ros = 
@@ -59,12 +62,14 @@
                 moveit-msgs
                 moveit-ros-planning
                 moveit-ros-planning-interface
+                gazebo
                 # rbs-skill-interfaces
               ]) ++ (with pkgs; [ nlohmann_json ]);
               RMW_IMPLEMENTATION = "rmw_fastrtps_dynamic_cpp";
             };
 
           devShells.bpy = pkgs.mkShell { packages = [ bpy ]; };
+          devShells.pysdf = pkgs.mkShell { packages = [ pysdf ]; };
           devShells.blender = pkgs.mkShell { packages = [ blender ]; };
         }
       );
diff --git a/pkgs/development/python-modules/pysdf/default.nix b/pkgs/development/python-modules/pysdf/default.nix
new file mode 100644
index 0000000..adbda23
--- /dev/null
+++ b/pkgs/development/python-modules/pysdf/default.nix
@@ -0,0 +1,13 @@
+{ buildPythonPackage, fetchFromGitHub, python3Packages }:
+buildPythonPackage {
+  format = "pyproject";
+  pname = "pysdf";
+  version = "0.4";
+  src = fetchFromGitHub {
+    owner = "movefasta";
+    repo = "python-sdformat";
+    rev = "edfa3bdb97598c11d83bd5d9473db12ef645a478";
+    sha256 = "sha256-4IuljqprFK15B356Iuibz1pphvQWkrtvLsqTntuTB/o=";
+  };
+  propagatedBuildInputs = with python3Packages; [ poetry-core lxml numpy pytest black ];
+}