diff --git a/.gitlab/ci/configure_common.cmake b/.gitlab/ci/configure_common.cmake
index cda016490398be357aab016d2b4cd6dac9e2a30a..d929e2f28a159c19e96d3ce7841e19c9429c1206 100644
--- a/.gitlab/ci/configure_common.cmake
+++ b/.gitlab/ci/configure_common.cmake
@@ -142,13 +142,6 @@ else ()
   set(ENABLE_smtk "ON" CACHE BOOL "")
   set(ENABLE_smtkresourcemanagerstate "OFF" CACHE BOOL "")
 
-  if ("$ENV{CI_JOB_NAME}" MATCHES "centos7")
-    # matplotlib is not necessary, but this is as good a place as any to test it
-    set(ENABLE_matplotlib "ON" CACHE BOOL "")
-  else ()
-    set(ENABLE_matplotlib "OFF" CACHE BOOL "")
-  endif ()
-
   if ("$ENV{CMAKE_CONFIGURATION}" MATCHES "smtk")
     set(ENABLE_paraview "ON" CACHE BOOL "")
   elseif ("$ENV{CMAKE_CONFIGURATION}" MATCHES "vtk")
diff --git a/projects/paraview.cmake b/projects/paraview.cmake
index 2e5b6008e2f51b8c2700b3020d3e0a111375eb90..fad4aacaeda278005315b94a3c8fdaef639be415 100644
--- a/projects/paraview.cmake
+++ b/projects/paraview.cmake
@@ -86,7 +86,7 @@ superbuild_add_project(paraview
     netcdf
   DEPENDS_OPTIONAL
     cxx11 hdf5 protobuf las gdal
-    python3 tbb
+    python3 tbb nlohmannjson
   CMAKE_ARGS
     -DPARAVIEW_BUILD_SHARED_LIBS:BOOL=ON
     -DPARAVIEW_BUILD_TESTING:BOOL=OFF
diff --git a/projects/vtkonly.cmake b/projects/vtkonly.cmake
index b8bb362e151bbb1a2f382d490b377fe6db8fc4c8..07b30a858580c865bb836fc70ab6e67777c21e4a 100644
--- a/projects/vtkonly.cmake
+++ b/projects/vtkonly.cmake
@@ -60,6 +60,7 @@ superbuild_add_project(vtkonly
     netcdf
   DEPENDS_OPTIONAL
     cxx11 freetype gdal libarchive python3 qt5 hdf5 las tbb
+    nlohmannjson
   CMAKE_ARGS
     -DBUILD_SHARED_LIBS:BOOL=ON
     -DVTK_BUILD_TESTING:BOOL=OFF
@@ -69,6 +70,11 @@ superbuild_add_project(vtkonly
     -DVTK_UNIFIED_INSTALL_TREE:BOOL=ON
     -DVTK_DLL_PATHS:STRING=${vtk_dll_paths}
 
+    # When a superbuild pkgconf is used, it assumes that its prefix is searched
+    # for by the toolchain by default. This is not the case, so keep system
+    # cflags.
+    -DPKG_CONFIG_ARGN=--keep-system-cflags
+
     -DVTK_MODULE_ENABLE_VTK_GUISupportQt:STRING=${vtkonly_qt_req}
     # CMB needs geovis enabled to provide the gdal reader
     -DVTK_MODULE_ENABLE_VTK_CommonArchive:STRING=${vtkonly_libarchive_req}
@@ -90,6 +96,7 @@ superbuild_add_project(vtkonly
     -DVTK_MODULE_USE_EXTERNAL_VTK_netcdf:BOOL=${netcdf_enabled}
     -DVTK_MODULE_USE_EXTERNAL_VTK_png:BOOL=${png_enabled}
     -DVTK_MODULE_USE_EXTERNAL_VTK_zlib:BOOL=${zlib_enabled}
+    -DVTK_MODULE_USE_EXTERNAL_VTK_nlohmannjson:BOOL=${nlohmannjson_enabled}
 
     -DVTK_GROUP_ENABLE_Web:STRING=${vtkonly_python_req}
     -DVTK_SMP_IMPLEMENTATION_TYPE:STRING=${vtk_smp_backend}