diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 00000000..07334249
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "neo/extern/glslang"]
+	path = neo/extern/glslang
+	url = https://github.com/KhronosGroup/glslang.git
diff --git a/neo/CMakeLists.txt b/neo/CMakeLists.txt
index 9450dcc9..14f14ef6 100644
--- a/neo/CMakeLists.txt
+++ b/neo/CMakeLists.txt
@@ -309,17 +309,21 @@ if(USE_VULKAN)
 
 	else()
 		# override Glslang build options
+		
+		# options required by November 2018 release
 		SET_OPTION(ENABLE_SPVREMAPPER OFF)
 		SET_OPTION(ENABLE_GLSLANG_BINARIES OFF)
 		SET_OPTION(ENABLE_HLSL OFF)
 		SET_OPTION(ENABLE_OPT ON)
 		SET_OPTION(SPIRV_SKIP_EXECUTABLES ON)
+		
+		# options required by November 2019 release
+		#SET_OPTION(ENABLE_PCH OFF)
+		#SET_OPTION(ENABLE_CTEST OFF)
+		#SET_OPTION(BUILD_EXTERNAL OFF)
+		#SET_OPTION(SKIP_GLSLANG_INSTALL ON)
 	
-		#option(ENABLE_AMD_EXTENSIONS "Enables support of AMD-specific extensions" ON)
-		#option(ENABLE_NV_EXTENSIONS "Enables support of Nvidia-specific extensions" ON)
-		#option(ENABLE_OPT "Enables spirv-opt capability if present" ON)
-	
-		set(GLSLANG_DIR ${CMAKE_CURRENT_SOURCE_DIR}/libs/glslang)
+		set(GLSLANG_DIR ${CMAKE_CURRENT_SOURCE_DIR}/extern/glslang)
 		add_subdirectory(${GLSLANG_DIR})
 	
 		include_directories(${GLSLANG_DIR}/glslang)
diff --git a/neo/astyle-code.bat b/neo/astyle-code.bat
index d180dc12..ea40b02a 100644
--- a/neo/astyle-code.bat
+++ b/neo/astyle-code.bat
@@ -1,5 +1,5 @@
-astyle.exe -v --formatted --options=astyle-options.ini --exclude="libs" --recursive *.h
-astyle.exe -v --formatted --options=astyle-options.ini --exclude="libs" --exclude="d3xp/gamesys/SysCvar.cpp" --exclude="d3xp/gamesys/Callbacks.cpp" --exclude="sys/win32/win_cpu.cpp" --exclude="sys/win32/win_main.cpp" --recursive *.cpp
+astyle.exe -v --formatted --options=astyle-options.ini --exclude="libs" --exclude="extern" --recursive *.h
+astyle.exe -v --formatted --options=astyle-options.ini --exclude="libs" --exclude="extern" --exclude="d3xp/gamesys/SysCvar.cpp" --exclude="d3xp/gamesys/Callbacks.cpp" --exclude="sys/win32/win_cpu.cpp" --exclude="sys/win32/win_main.cpp" --recursive *.cpp
 
 astyle.exe -v --formatted --options=astyle-options.ini --recursive libs/imgui/*.h
 astyle.exe -v --formatted --options=astyle-options.ini --recursive libs/imgui/*.cpp
diff --git a/neo/astyle-code.sh b/neo/astyle-code.sh
index 0e7ad74d..f01c8654 100755
--- a/neo/astyle-code.sh
+++ b/neo/astyle-code.sh
@@ -34,6 +34,6 @@ if [ "$ASTYLE_VERSION" != "$OUR_ASTYLE_VERSION" ]; then
 	exit 1
 fi
 
-$ASTYLE_BIN -v --formatted --options=astyle-options.ini --exclude="libs" --recursive "*.h"
-$ASTYLE_BIN -v --formatted --options=astyle-options.ini --exclude="libs" --exclude="d3xp/gamesys/SysCvar.cpp" --exclude="d3xp/gamesys/Callbacks.cpp" \
+$ASTYLE_BIN -v --formatted --options=astyle-options.ini --exclude="libs" --exclude="extern" --recursive "*.h"
+$ASTYLE_BIN -v --formatted --options=astyle-options.ini --exclude="libs" --exclude="extern" --exclude="d3xp/gamesys/SysCvar.cpp" --exclude="d3xp/gamesys/Callbacks.cpp" \
 		--exclude="sys/win32/win_cpu.cpp" --exclude="sys/win32/win_main.cpp" --recursive "*.cpp"
diff --git a/neo/extern/glslang b/neo/extern/glslang
new file mode 160000
index 00000000..1bc601c6
--- /dev/null
+++ b/neo/extern/glslang
@@ -0,0 +1 @@
+Subproject commit 1bc601c674aecc2fee0dee8ff7a118db76b4c439
diff --git a/neo/renderer/Vulkan/RenderBackend_VK.cpp b/neo/renderer/Vulkan/RenderBackend_VK.cpp
index ace79bac..4e01e4f0 100644
--- a/neo/renderer/Vulkan/RenderBackend_VK.cpp
+++ b/neo/renderer/Vulkan/RenderBackend_VK.cpp
@@ -45,7 +45,7 @@ idCVar r_syncEveryFrame( "r_syncEveryFrame", "1", CVAR_BOOL, "Don't let the GPU
 
 // NEW VULKAN STUFF
 
-idCVar r_vkEnableValidationLayers( "r_vkEnableValidationLayers", "0", CVAR_BOOL, "" );
+idCVar r_vkEnableValidationLayers( "r_vkEnableValidationLayers", "0", CVAR_BOOL | CVAR_INIT, "" );
 
 vulkanContext_t vkcontext;
 
diff --git a/neo/renderer/Vulkan/RenderProgs_VK.cpp b/neo/renderer/Vulkan/RenderProgs_VK.cpp
index 829a10c2..e7af84dd 100644
--- a/neo/renderer/Vulkan/RenderProgs_VK.cpp
+++ b/neo/renderer/Vulkan/RenderProgs_VK.cpp
@@ -409,6 +409,8 @@ namespace glslang
 #if 0
 extern const TBuiltInResource DefaultTBuiltInResource;
 #else
+
+// RB: see RBDOOM-3-BFG\neo\extern\glslang\StandAlone\ResourceLimits.cpp
 const TBuiltInResource DefaultTBuiltInResource =
 {
 	/* .MaxLights = */ 32,
@@ -494,6 +496,16 @@ const TBuiltInResource DefaultTBuiltInResource =
 	/* .MaxCullDistances = */ 8,
 	/* .MaxCombinedClipAndCullDistances = */ 8,
 	/* .MaxSamples = */ 4,
+	/* .maxMeshOutputVerticesNV = */ 256,
+	/* .maxMeshOutputPrimitivesNV = */ 512,
+	/* .maxMeshWorkGroupSizeX_NV = */ 32,
+	/* .maxMeshWorkGroupSizeY_NV = */ 1,
+	/* .maxMeshWorkGroupSizeZ_NV = */ 1,
+	/* .maxTaskWorkGroupSizeX_NV = */ 32,
+	/* .maxTaskWorkGroupSizeY_NV = */ 1,
+	/* .maxTaskWorkGroupSizeZ_NV = */ 1,
+	/* .maxMeshViewCountNV = */ 4,
+
 	/* .limits = */ {
 		/* .nonInductiveForLoops = */ 1,
 		/* .whileLoops = */ 1,