diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 35cd65592..7ae6248e9 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -464,32 +464,32 @@ endif()
 	
 set( PLAT_POSIX_SOURCES
 	posix/i_steam.cpp
-	posix/i_system_posix.cpp )
+	common/platform/posix/i_system_posix.cpp )
 set( PLAT_SDL_SOURCES
-	posix/sdl/crashcatcher.c
-	posix/sdl/hardware.cpp
-	posix/sdl/i_gui.cpp
-	posix/sdl/i_input.cpp
-	posix/sdl/i_joystick.cpp
-	posix/sdl/i_main.cpp
-	posix/sdl/i_system.cpp
-	posix/sdl/sdlglvideo.cpp
-	posix/sdl/st_start.cpp )
+	common/platform/posix/sdl/crashcatcher.c
+	common/platform/posix/sdl/hardware.cpp
+	common/platform/posix/sdl/i_gui.cpp
+	common/platform/posix/sdl/i_input.cpp
+	common/platform/posix/sdl/i_joystick.cpp
+	common/platform/posix/sdl/i_main.cpp
+	common/platform/posix/sdl/i_system.cpp
+	common/platform/posix/sdl/sdlglvideo.cpp
+	common/platform/posix/sdl/st_start.cpp )
 set( PLAT_UNIX_SOURCES
-	posix/unix/i_specialpaths.cpp
-	posix/unix/gtk_dialogs.cpp )
+	common/platform/posix/unix/i_specialpaths.cpp
+	common/platform/posix/unix/gtk_dialogs.cpp )
 set( PLAT_OSX_SOURCES
-	posix/osx/iwadpicker_cocoa.mm
-	posix/osx/i_specialpaths.mm
+	common/platform/posix/osx/iwadpicker_cocoa.mm
+	common/platform/posix/osx/i_specialpaths.mm
 	posix/osx/zdoom.icns )
 set( PLAT_COCOA_SOURCES
-	posix/cocoa/i_input.mm
-	posix/cocoa/i_joystick.cpp
-	posix/cocoa/i_main.mm
-	posix/cocoa/i_system.mm
-	posix/cocoa/i_video.mm
-	posix/cocoa/st_console.mm
-	posix/cocoa/st_start.mm )
+	common/platform/posix/cocoa/i_input.mm
+	common/platform/posix/cocoa/i_joystick.cpp
+	common/platform/posix/cocoa/i_main.mm
+	common/platform/posix/cocoa/i_system.mm
+	common/platform/posix/cocoa/i_video.mm
+	common/platform/posix/cocoa/st_console.mm
+	common/platform/posix/cocoa/st_start.mm )
 
 if( WIN32 )
 	set( SYSTEM_SOURCES_DIR win32 )
@@ -499,22 +499,22 @@ if( WIN32 )
 	set( SYSTEM_SOURCES ${SYSTEM_SOURCES} win32/zdoom.rc )
 elseif( APPLE )
 	if( OSX_COCOA_BACKEND )
-		set( SYSTEM_SOURCES_DIR posix posix/cocoa )
+		set( SYSTEM_SOURCES_DIR common/platform/posix common/platform/posix/cocoa )
 		set( SYSTEM_SOURCES ${PLAT_COCOA_SOURCES} )
 		set( OTHER_SYSTEM_SOURCES ${PLAT_WIN32_SOURCES} ${PLAT_SDL_SOURCES} ${PLAT_UNIX_SOURCES} )
 	else()
-		set( SYSTEM_SOURCES_DIR posix posix/sdl )
+		set( SYSTEM_SOURCES_DIR common/platform/posix common/platform/posix/sdl )
 		set( SYSTEM_SOURCES ${PLAT_SDL_SOURCES} )
-		set( PLAT_OSX_SOURCES ${PLAT_OSX_SOURCES} posix/sdl/i_system.mm )
+		set( PLAT_OSX_SOURCES ${PLAT_OSX_SOURCES} common/platform/posix/sdl/i_system.mm )
 		set( OTHER_SYSTEM_SOURCES ${PLAT_WIN32_SOURCES} ${PLAT_COCOA_SOURCES} ${PLAT_UNIX_SOURCES} )
 	endif()
 
 	set( SYSTEM_SOURCES ${SYSTEM_SOURCES} ${PLAT_POSIX_SOURCES} ${PLAT_OSX_SOURCES} )
 
 	set_source_files_properties( posix/osx/zdoom.icns PROPERTIES MACOSX_PACKAGE_LOCATION Resources )
-	set_source_files_properties( posix/osx/iwadpicker_cocoa.mm PROPERTIES COMPILE_FLAGS -fobjc-exceptions )
+	set_source_files_properties( common/platform/posix/osx/iwadpicker_cocoa.mm PROPERTIES COMPILE_FLAGS -fobjc-exceptions )
 else()
-	set( SYSTEM_SOURCES_DIR posix posix/sdl )
+	set( SYSTEM_SOURCES_DIR common/platform/posix common/platform/posix/sdl )
 	set( SYSTEM_SOURCES ${PLAT_POSIX_SOURCES} ${PLAT_SDL_SOURCES} ${PLAT_UNIX_SOURCES} )
 	set( OTHER_SYSTEM_SOURCES ${PLAT_WIN32_SOURCES} ${PLAT_OSX_SOURCES} ${PLAT_COCOA_SOURCES} )
 endif()
@@ -594,8 +594,6 @@ file( GLOB HEADER_FILES
 	sound/*.h
 	sound/backend/*.h*
 	posix/*.h
-	posix/cocoa/*.h
-	posix/sdl/*.h
 	win32/*.h
 	r_data/*.h
 	r_data/models/*.h
@@ -610,6 +608,8 @@ file( GLOB HEADER_FILES
 	common/fonts/*.h
 	common/objects/*.h
 	common/filesystem/*.h
+	common/platform/posix/cocoa/*.h
+	common/platform/posix/sdl/*.h
 	common/textures/*.h
 	common/textures/hires/hqnx/*.h
 	common/textures/hires/hqnx_asm/*.h
@@ -1441,10 +1441,6 @@ source_group("Render Data" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/r_da
 source_group("Render Data\\Models" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/r_data/models/.+")
 source_group("Render Interface" FILES r_defs.h r_renderer.h r_sky.cpp r_sky.h r_state.h r_utility.cpp r_utility.h)
 source_group("Platforms\\POSIX Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/posix/.+")
-source_group("Platforms\\Cocoa Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/posix/cocoa/.+")
-source_group("Platforms\\OS X Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/posix/osx/.+")
-source_group("Platforms\\Unix Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/posix/unix/.+")
-source_group("Platforms\\SDL Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/posix/sdl/.+")
 source_group("Platforms\\Win32 Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/win32/.+")
 source_group("Scripting\\Decorate frontend" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/scripting/decorate/.+")
 source_group("Scripting\\ZScript frontend" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/scripting/zscript/.+")
@@ -1470,6 +1466,10 @@ source_group("Common\\Scripting\\Backend" REGULAR_EXPRESSION "^${CMAKE_CURRENT_S
 source_group("Common\\Scripting\\Core" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/scripting/core/.+")
 source_group("Common\\Scripting\\JIT" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/scripting/jit/.+")
 source_group("Common\\Scripting\\VM" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/scripting/vm/.+")
+source_group("Common\\Platforms\\Cocoa Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/platform/posix/cocoa/.+")
+source_group("Common\\Platforms\\OS X Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/platform/posix/osx/.+")
+source_group("Common\\Platforms\\Unix Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/platform/posix/unix/.+")
+source_group("Common\\Platforms\\SDL Files" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/platform/posix/sdl/.+")
 source_group("Common\\Rendering" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/rendering/.+")
 source_group("Common\\Rendering\\OpenGL Loader" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/rendering/gl_load/.+")
 source_group("Common\\Textures" REGULAR_EXPRESSION "^${CMAKE_CURRENT_SOURCE_DIR}/common/textures/.+")
diff --git a/src/common/audio/sound/i_soundinternal.h b/src/common/audio/sound/i_soundinternal.h
index 36ccd52c0..be3486440 100644
--- a/src/common/audio/sound/i_soundinternal.h
+++ b/src/common/audio/sound/i_soundinternal.h
@@ -146,4 +146,5 @@ class SoundStream;
 
 void S_SetSoundPaused(int state);
 
+
 #endif
diff --git a/src/g_input.h b/src/common/engine/g_input.h
similarity index 100%
rename from src/g_input.h
rename to src/common/engine/g_input.h
diff --git a/src/posix/cocoa/gl_sysfb.h b/src/common/platform/posix/cocoa/gl_sysfb.h
similarity index 100%
rename from src/posix/cocoa/gl_sysfb.h
rename to src/common/platform/posix/cocoa/gl_sysfb.h
diff --git a/src/posix/cocoa/i_common.h b/src/common/platform/posix/cocoa/i_common.h
similarity index 100%
rename from src/posix/cocoa/i_common.h
rename to src/common/platform/posix/cocoa/i_common.h
diff --git a/src/posix/cocoa/i_input.mm b/src/common/platform/posix/cocoa/i_input.mm
similarity index 100%
rename from src/posix/cocoa/i_input.mm
rename to src/common/platform/posix/cocoa/i_input.mm
diff --git a/src/posix/cocoa/i_joystick.cpp b/src/common/platform/posix/cocoa/i_joystick.cpp
similarity index 100%
rename from src/posix/cocoa/i_joystick.cpp
rename to src/common/platform/posix/cocoa/i_joystick.cpp
diff --git a/src/posix/cocoa/i_main.mm b/src/common/platform/posix/cocoa/i_main.mm
similarity index 100%
rename from src/posix/cocoa/i_main.mm
rename to src/common/platform/posix/cocoa/i_main.mm
diff --git a/src/posix/cocoa/i_system.mm b/src/common/platform/posix/cocoa/i_system.mm
similarity index 100%
rename from src/posix/cocoa/i_system.mm
rename to src/common/platform/posix/cocoa/i_system.mm
diff --git a/src/posix/cocoa/i_video.mm b/src/common/platform/posix/cocoa/i_video.mm
similarity index 100%
rename from src/posix/cocoa/i_video.mm
rename to src/common/platform/posix/cocoa/i_video.mm
diff --git a/src/posix/cocoa/st_console.h b/src/common/platform/posix/cocoa/st_console.h
similarity index 100%
rename from src/posix/cocoa/st_console.h
rename to src/common/platform/posix/cocoa/st_console.h
diff --git a/src/posix/cocoa/st_console.mm b/src/common/platform/posix/cocoa/st_console.mm
similarity index 100%
rename from src/posix/cocoa/st_console.mm
rename to src/common/platform/posix/cocoa/st_console.mm
diff --git a/src/posix/cocoa/st_start.mm b/src/common/platform/posix/cocoa/st_start.mm
similarity index 100%
rename from src/posix/cocoa/st_start.mm
rename to src/common/platform/posix/cocoa/st_start.mm
diff --git a/src/posix/dikeys.h b/src/common/platform/posix/dikeys.h
similarity index 100%
rename from src/posix/dikeys.h
rename to src/common/platform/posix/dikeys.h
diff --git a/src/posix/hardware.h b/src/common/platform/posix/hardware.h
similarity index 100%
rename from src/posix/hardware.h
rename to src/common/platform/posix/hardware.h
diff --git a/src/posix/i_system.h b/src/common/platform/posix/i_system.h
similarity index 100%
rename from src/posix/i_system.h
rename to src/common/platform/posix/i_system.h
diff --git a/src/posix/i_system_posix.cpp b/src/common/platform/posix/i_system_posix.cpp
similarity index 100%
rename from src/posix/i_system_posix.cpp
rename to src/common/platform/posix/i_system_posix.cpp
diff --git a/src/posix/osx/i_specialpaths.mm b/src/common/platform/posix/osx/i_specialpaths.mm
similarity index 100%
rename from src/posix/osx/i_specialpaths.mm
rename to src/common/platform/posix/osx/i_specialpaths.mm
diff --git a/src/posix/osx/iwadpicker_cocoa.mm b/src/common/platform/posix/osx/iwadpicker_cocoa.mm
similarity index 100%
rename from src/posix/osx/iwadpicker_cocoa.mm
rename to src/common/platform/posix/osx/iwadpicker_cocoa.mm
diff --git a/src/posix/readme.md b/src/common/platform/posix/readme.md
similarity index 100%
rename from src/posix/readme.md
rename to src/common/platform/posix/readme.md
diff --git a/src/posix/sdl/crashcatcher.c b/src/common/platform/posix/sdl/crashcatcher.c
similarity index 100%
rename from src/posix/sdl/crashcatcher.c
rename to src/common/platform/posix/sdl/crashcatcher.c
diff --git a/src/posix/sdl/gl_sysfb.h b/src/common/platform/posix/sdl/gl_sysfb.h
similarity index 100%
rename from src/posix/sdl/gl_sysfb.h
rename to src/common/platform/posix/sdl/gl_sysfb.h
diff --git a/src/posix/sdl/hardware.cpp b/src/common/platform/posix/sdl/hardware.cpp
similarity index 100%
rename from src/posix/sdl/hardware.cpp
rename to src/common/platform/posix/sdl/hardware.cpp
diff --git a/src/posix/sdl/i_gui.cpp b/src/common/platform/posix/sdl/i_gui.cpp
similarity index 100%
rename from src/posix/sdl/i_gui.cpp
rename to src/common/platform/posix/sdl/i_gui.cpp
diff --git a/src/posix/sdl/i_input.cpp b/src/common/platform/posix/sdl/i_input.cpp
similarity index 100%
rename from src/posix/sdl/i_input.cpp
rename to src/common/platform/posix/sdl/i_input.cpp
diff --git a/src/posix/sdl/i_joystick.cpp b/src/common/platform/posix/sdl/i_joystick.cpp
similarity index 100%
rename from src/posix/sdl/i_joystick.cpp
rename to src/common/platform/posix/sdl/i_joystick.cpp
diff --git a/src/posix/sdl/i_main.cpp b/src/common/platform/posix/sdl/i_main.cpp
similarity index 100%
rename from src/posix/sdl/i_main.cpp
rename to src/common/platform/posix/sdl/i_main.cpp
diff --git a/src/posix/sdl/i_system.cpp b/src/common/platform/posix/sdl/i_system.cpp
similarity index 100%
rename from src/posix/sdl/i_system.cpp
rename to src/common/platform/posix/sdl/i_system.cpp
diff --git a/src/posix/sdl/i_system.mm b/src/common/platform/posix/sdl/i_system.mm
similarity index 100%
rename from src/posix/sdl/i_system.mm
rename to src/common/platform/posix/sdl/i_system.mm
diff --git a/src/posix/sdl/sdlglvideo.cpp b/src/common/platform/posix/sdl/sdlglvideo.cpp
similarity index 100%
rename from src/posix/sdl/sdlglvideo.cpp
rename to src/common/platform/posix/sdl/sdlglvideo.cpp
diff --git a/src/posix/sdl/st_start.cpp b/src/common/platform/posix/sdl/st_start.cpp
similarity index 100%
rename from src/posix/sdl/st_start.cpp
rename to src/common/platform/posix/sdl/st_start.cpp
diff --git a/src/posix/unix/gtk_dialogs.cpp b/src/common/platform/posix/unix/gtk_dialogs.cpp
similarity index 100%
rename from src/posix/unix/gtk_dialogs.cpp
rename to src/common/platform/posix/unix/gtk_dialogs.cpp
diff --git a/src/posix/unix/i_specialpaths.cpp b/src/common/platform/posix/unix/i_specialpaths.cpp
similarity index 100%
rename from src/posix/unix/i_specialpaths.cpp
rename to src/common/platform/posix/unix/i_specialpaths.cpp