diff --git a/crystal/osrf-pycommon/default.nix b/crystal/osrf-pycommon/default.nix
index 1cbfcac356..b85945ee86 100644
--- a/crystal/osrf-pycommon/default.nix
+++ b/crystal/osrf-pycommon/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl,  }:
+{ lib, buildRosPackage, fetchurl, python3Packages }:
 buildRosPackage {
   pname = "ros-crystal-osrf-pycommon";
   version = "0.1.6";
@@ -14,6 +14,7 @@ buildRosPackage {
   };
 
   buildType = "ament_python";
+  propagatedBuildInputs = [ python3Packages.mock ];
 
   meta = {
     description = ''Commonly needed Python modules, used by Python software developed at OSRF.'';
diff --git a/dashing/osrf-pycommon/default.nix b/dashing/osrf-pycommon/default.nix
index 349ac3acfe..ab8e68bf4e 100644
--- a/dashing/osrf-pycommon/default.nix
+++ b/dashing/osrf-pycommon/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl,  }:
+{ lib, buildRosPackage, fetchurl, python3Packages }:
 buildRosPackage {
   pname = "ros-dashing-osrf-pycommon";
   version = "0.1.9-r1";
@@ -14,6 +14,7 @@ buildRosPackage {
   };
 
   buildType = "ament_python";
+  propagatedBuildInputs = [ python3Packages.mock ];
 
   meta = {
     description = ''Commonly needed Python modules, used by Python software developed at OSRF.'';
diff --git a/kinetic/resource-retriever/default.nix b/kinetic/resource-retriever/default.nix
index e8463e0f35..0f8f4bfa68 100644
--- a/kinetic/resource-retriever/default.nix
+++ b/kinetic/resource-retriever/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, rosconsole, boost, catkin, curl, roslib }:
+{ lib, buildRosPackage, fetchurl, rosconsole, boost, catkin, pythonPackages, curl, roslib }:
 buildRosPackage {
   pname = "ros-kinetic-resource-retriever";
   version = "1.12.5-r1";
@@ -15,7 +15,7 @@ buildRosPackage {
 
   buildType = "catkin";
   buildInputs = [ curl roslib rosconsole boost ];
-  propagatedBuildInputs = [ curl roslib rosconsole boost ];
+  propagatedBuildInputs = [ rosconsole boost pythonPackages.rospkg curl roslib ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/catkin/default.nix b/melodic/catkin/default.nix
index 4c463845dc..db4bdb7f1b 100644
--- a/melodic/catkin/default.nix
+++ b/melodic/catkin/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, gtest, cmake, gmock }:
+{ lib, buildRosPackage, fetchurl, python, gtest, pythonPackages, cmake, gmock }:
 buildRosPackage {
   pname = "ros-melodic-catkin";
   version = "0.7.19-r1";
@@ -14,7 +14,9 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  propagatedBuildInputs = [ gtest cmake gmock ];
+  buildInputs = [ python pythonPackages.catkin-pkg pythonPackages.empy ];
+  checkInputs = [ pythonPackages.nose pythonPackages.mock ];
+  propagatedBuildInputs = [ python pythonPackages.nose gtest pythonPackages.catkin-pkg cmake gmock pythonPackages.empy ];
   nativeBuildInputs = [ cmake ];
 
   meta = {
diff --git a/melodic/genpy/default.nix b/melodic/genpy/default.nix
index d615e83e1e..63b6872071 100644
--- a/melodic/genpy/default.nix
+++ b/melodic/genpy/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, genmsg, catkin }:
+{ lib, buildRosPackage, fetchurl, genmsg, catkin, pythonPackages }:
 buildRosPackage {
   pname = "ros-melodic-genpy";
   version = "0.6.9-r1";
@@ -15,7 +15,7 @@ buildRosPackage {
 
   buildType = "catkin";
   buildInputs = [ genmsg ];
-  propagatedBuildInputs = [ genmsg ];
+  propagatedBuildInputs = [ genmsg pythonPackages.pyyaml ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/python-qt-binding/default.nix b/melodic/python-qt-binding/default.nix
index 97c096a1b1..784416d243 100644
--- a/melodic/python-qt-binding/default.nix
+++ b/melodic/python-qt-binding/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, catkin, qt5, rosbuild }:
+{ lib, buildRosPackage, fetchurl, catkin, rosbuild, pythonPackages, qt5 }:
 buildRosPackage {
   pname = "ros-melodic-python-qt-binding";
   version = "0.3.6-r2";
@@ -14,8 +14,8 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  buildInputs = [ rosbuild qt5.qtbase ];
-  propagatedBuildInputs = [ catkin ];
+  buildInputs = [ pythonPackages.pyqt5 rosbuild qt5.qtbase ];
+  propagatedBuildInputs = [ pythonPackages.pyqt5 catkin ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/qt-dotgraph/default.nix b/melodic/qt-dotgraph/default.nix
index e1f286927b..4531b2eeb1 100644
--- a/melodic/qt-dotgraph/default.nix
+++ b/melodic/qt-dotgraph/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, catkin, python-qt-binding }:
+{ lib, buildRosPackage, fetchurl, catkin, pythonPackages, python-qt-binding }:
 buildRosPackage {
   pname = "ros-melodic-qt-dotgraph";
   version = "0.3.15-r1";
@@ -14,7 +14,8 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  propagatedBuildInputs = [ python-qt-binding ];
+  checkInputs = [ pythonPackages.pygraphviz ];
+  propagatedBuildInputs = [ pythonPackages.pydot python-qt-binding ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/qt-gui-py-common/default.nix b/melodic/qt-gui-py-common/default.nix
index b770a56a2c..636f91c112 100644
--- a/melodic/qt-gui-py-common/default.nix
+++ b/melodic/qt-gui-py-common/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, catkin, python-qt-binding }:
+{ lib, buildRosPackage, fetchurl, catkin, pythonPackages, python-qt-binding }:
 buildRosPackage {
   pname = "ros-melodic-qt-gui-py-common";
   version = "0.3.15-r1";
@@ -14,7 +14,7 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  propagatedBuildInputs = [ python-qt-binding ];
+  propagatedBuildInputs = [ pythonPackages.rospkg python-qt-binding ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/qt-gui/default.nix b/melodic/qt-gui/default.nix
index a9fbc932f5..921a336510 100644
--- a/melodic/qt-gui/default.nix
+++ b/melodic/qt-gui/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, catkin, python-qt-binding, qt5, tango-icon-theme }:
+{ lib, buildRosPackage, fetchurl, catkin, pythonPackages, qt5, python-qt-binding, tango-icon-theme }:
 buildRosPackage {
   pname = "ros-melodic-qt-gui";
   version = "0.3.15-r1";
@@ -14,8 +14,8 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  buildInputs = [ qt5.qtbase ];
-  propagatedBuildInputs = [ python-qt-binding tango-icon-theme ];
+  buildInputs = [ pythonPackages.pyqt5 qt5.qtbase ];
+  propagatedBuildInputs = [ pythonPackages.rospkg python-qt-binding tango-icon-theme ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/resource-retriever/default.nix b/melodic/resource-retriever/default.nix
index 0d0f6cb612..b513600e3a 100644
--- a/melodic/resource-retriever/default.nix
+++ b/melodic/resource-retriever/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, rosconsole, boost, catkin, curl, roslib }:
+{ lib, buildRosPackage, fetchurl, rosconsole, boost, catkin, pythonPackages, curl, roslib }:
 buildRosPackage {
   pname = "ros-melodic-resource-retriever";
   version = "1.12.5-r1";
@@ -15,7 +15,7 @@ buildRosPackage {
 
   buildType = "catkin";
   buildInputs = [ curl roslib rosconsole boost ];
-  propagatedBuildInputs = [ curl roslib rosconsole boost ];
+  propagatedBuildInputs = [ rosconsole boost pythonPackages.rospkg curl roslib ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/rosclean/default.nix b/melodic/rosclean/default.nix
index 56b0a35e86..fdbca75bcb 100644
--- a/melodic/rosclean/default.nix
+++ b/melodic/rosclean/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, catkin }:
+{ lib, buildRosPackage, fetchurl, catkin, pythonPackages }:
 buildRosPackage {
   pname = "ros-melodic-rosclean";
   version = "1.14.7-r1";
@@ -14,6 +14,7 @@ buildRosPackage {
   };
 
   buildType = "catkin";
+  propagatedBuildInputs = [ pythonPackages.rospkg ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/roscreate/default.nix b/melodic/roscreate/default.nix
index af85a6e79b..588c701c63 100644
--- a/melodic/roscreate/default.nix
+++ b/melodic/roscreate/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, roslib, catkin }:
+{ lib, buildRosPackage, fetchurl, roslib, catkin, pythonPackages }:
 buildRosPackage {
   pname = "ros-melodic-roscreate";
   version = "1.14.7-r1";
@@ -14,7 +14,7 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  propagatedBuildInputs = [ roslib ];
+  propagatedBuildInputs = [ pythonPackages.rospkg roslib ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/roslib/default.nix b/melodic/roslib/default.nix
index ffbf3780de..7855e3f23a 100644
--- a/melodic/roslib/default.nix
+++ b/melodic/roslib/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, ros-environment, rospack, boost, catkin, rosmake }:
+{ lib, buildRosPackage, fetchurl, ros-environment, rospack, boost, catkin, pythonPackages, rosmake }:
 buildRosPackage {
   pname = "ros-melodic-roslib";
   version = "1.14.7-r1";
@@ -16,7 +16,7 @@ buildRosPackage {
   buildType = "catkin";
   buildInputs = [ rospack boost ];
   checkInputs = [ rosmake ];
-  propagatedBuildInputs = [ ros-environment rospack catkin ];
+  propagatedBuildInputs = [ pythonPackages.rospkg ros-environment rospack catkin ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/rosmake/default.nix b/melodic/rosmake/default.nix
index 98dc6a0d76..bf4eda6a6e 100644
--- a/melodic/rosmake/default.nix
+++ b/melodic/rosmake/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, catkin }:
+{ lib, buildRosPackage, fetchurl, catkin, pythonPackages }:
 buildRosPackage {
   pname = "ros-melodic-rosmake";
   version = "1.14.7-r1";
@@ -14,7 +14,7 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  propagatedBuildInputs = [ catkin ];
+  propagatedBuildInputs = [ pythonPackages.rospkg catkin ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/rospack/default.nix b/melodic/rospack/default.nix
index 505786104f..59014817a0 100644
--- a/melodic/rospack/default.nix
+++ b/melodic/rospack/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, ros-environment, cmake-modules, boost, gtest, catkin, pkg-config, tinyxml-2 }:
+{ lib, buildRosPackage, fetchurl, python, ros-environment, cmake-modules, boost, gtest, catkin, pythonPackages, pkg-config, tinyxml-2 }:
 buildRosPackage {
   pname = "ros-melodic-rospack";
   version = "2.5.4-r1";
@@ -14,8 +14,9 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  buildInputs = [ cmake-modules boost gtest pkg-config tinyxml-2 ];
-  propagatedBuildInputs = [ ros-environment tinyxml-2 boost pkg-config ];
+  buildInputs = [ python cmake-modules boost gtest pkg-config tinyxml-2 ];
+  checkInputs = [ pythonPackages.coverage ];
+  propagatedBuildInputs = [ python ros-environment boost pythonPackages.rosdep pkg-config tinyxml-2 pythonPackages.catkin-pkg ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/rosunit/default.nix b/melodic/rosunit/default.nix
index bc16fdde10..383284d47e 100644
--- a/melodic/rosunit/default.nix
+++ b/melodic/rosunit/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, roslib, catkin }:
+{ lib, buildRosPackage, fetchurl, roslib, catkin, pythonPackages }:
 buildRosPackage {
   pname = "ros-melodic-rosunit";
   version = "1.14.7-r1";
@@ -14,7 +14,7 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  propagatedBuildInputs = [ roslib ];
+  propagatedBuildInputs = [ pythonPackages.rospkg roslib ];
   nativeBuildInputs = [ catkin ];
 
   meta = {
diff --git a/melodic/urdfdom-py/default.nix b/melodic/urdfdom-py/default.nix
index bb1ead7f27..e4d10f4b1f 100644
--- a/melodic/urdfdom-py/default.nix
+++ b/melodic/urdfdom-py/default.nix
@@ -2,7 +2,7 @@
 # Copyright 2019 Open Source Robotics Foundation
 # Distributed under the terms of the BSD license
 
-{ lib, buildRosPackage, fetchurl, catkin, rospy }:
+{ lib, buildRosPackage, fetchurl, catkin, pythonPackages, rospy }:
 buildRosPackage {
   pname = "ros-melodic-urdfdom-py";
   version = "0.4.1-r1";
@@ -14,7 +14,8 @@ buildRosPackage {
   };
 
   buildType = "catkin";
-  propagatedBuildInputs = [ rospy ];
+  checkInputs = [ pythonPackages.mock ];
+  propagatedBuildInputs = [ pythonPackages.lxml pythonPackages.pyyaml rospy ];
   nativeBuildInputs = [ catkin ];
 
   meta = {