diff --git a/GNUmakefile b/GNUmakefile
index 62863c8..3a8bb78 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -2,13 +2,6 @@
 
 PREFIX = /usr/local
 
-ifeq ($(TARGET),)
-TARGET = $(shell uname -s)
-endif
-ifneq ($(TARGET),$(shell uname -s))
-CROSS = 1
-endif
-
 USE_STB_IMAGE = 1
 USE_STB_TRUETYPE = 0
 USE_FREETYPE2 = 1
@@ -25,17 +18,6 @@ else
 CFLAGS += -O2
 endif
 
-ifeq ($(TARGET),NetBSD)
-VULKAN_NO_STRING_HELPER = 1
-endif
-
-ifeq ($(VULKAN_NO_STRING_HELPER),1)
-VK_STRING_HELPER_DEFINE =
-else
-VK_STRING_HELPER_DEFINE = -DHAS_VK_ENUM_STRING_HELPER
-endif
-CFLAGS += $(VK_STRING_HELPER_DEFINE)
-
 L_CFLAGS = $(DEPINC) $(CFLAGS) -fPIC -D_MILSKO
 L_LDFLAGS = $(LDFLAGS)
 L_LIBS = $(LIBS)
@@ -51,124 +33,15 @@ E_CFLAGS = $(CFLAGS)
 E_LDFLAGS = $(LDFLAGS) -Lsrc -Wl,-rpath,$(shell pwd)/src
 E_LIBS = $(LIBS) -lMw
 
-FOUND_PLATFORM = 0
-
-ifeq ($(TARGET),NetBSD)
-CFLAGS += -I/usr/X11R7/include -I/usr/pkg/include
-LDFLAGS += -L/usr/X11R7/lib -L/usr/pkg/lib -Wl,-R/usr/X11R7/lib -Wl,-R/usr/pkg/lib
-UNIX = 1
-OPENGL = 1
-VULKAN = 1
-FOUND_PLATFORM = 1
-endif
-
-ifeq ($(TARGET),Linux)
-L_LIBS += -ldl
-UNIX = 1
-OPENGL = 1
-VULKAN = 1
-FOUND_PLATFORM = 1
-endif
-
-ifeq ($(TARGET),Windows)
-WINDOWS = 1
-OPENGL = 1
-VULKAN = 1
-FOUND_PLATFORM = 1
-endif
-
-ifeq ($(TARGET),SunOS)
-CC = gcc
-UNIX = 1
-L_LIBS += -lsocket -lnsl
-OPENGL = 1
-FOUND_PLATFORM = 1
-endif
-
-ifeq ($(TARGET),Darwin)
-CC = gcc
-DARWIN = 1
-L_LIBS += -framework Carbon
-FOUND_PLATFORM = 1
-endif
-
-ifeq ($(FOUND_PLATFORM),0)
-$(error Add your platform definition)
-endif
-
-# Standard gcc accepts this but we have to override this for Apple's gcc.
-SHARED = -shared
-
-ifeq ($(UNIX),1)
-L_CFLAGS += -DUSE_X11 -DUNIX
-L_OBJS += src/backend/x11.o
-L_LIBS += -lm -lX11 -lXrender -lXcursor
-
-GL = -lGL -lGLU
-
-E_LIBS += -lm
-
-LIB = lib
-SO = .so
-EXEC =
-endif
-
-ifeq ($(WINDOWS),1)
-L_CFLAGS += -DUSE_GDI
-L_LDFLAGS += -Wl,--out-implib,src/libMw.a -static-libgcc
-L_OBJS += src/backend/gdi.o
-L_LIBS += -lgdi32
-
-GL = -lopengl32 -lglu32
-
-LIB =
-SO = .dll
-EXEC = .exe
-endif
-
-ifeq ($(DARWIN),1)
-L_CFLAGS += -DSTBI_NO_THREAD_LOCALS -DUSE_DARWIN
-L_OBJS += src/backend/mac/mac.o src/backend/mac/carbon.o
-
-LIB = lib
-SO = .dylib
-EXEC =
-
-SHARED = -dynamiclib
-endif
-
-ifeq ($(USE_STB_IMAGE),1)
-L_CFLAGS += -DUSE_STB_IMAGE
-else
-include external/deps.mk
-endif
-
-ifeq ($(USE_FREETYPE2),1)
-L_CFLAGS += -DUSE_FREETYPE2
-
-ifneq ($(CROSS),1)
-L_CFLAGS += $(shell pkg-config --cflags freetype2)
-L_LIBS += $(shell pkg-config --libs freetype2)
-endif
-endif
-
-ifeq ($(USE_STB_TRUETYPE),1)
-L_CFLAGS += -DUSE_STB_TRUETYPE
-endif
+include mk/platform.mk
+include mk/flags.mk
+include mk/stb.mk
+include mk/freetype2.mk
+include mk/opengl.mk
+include mk/vulkan.mk
 
 EXAMPLES = examples/basic/example$(EXEC) examples/basic/rotate$(EXEC) examples/basic/image$(EXEC) examples/basic/scrollbar$(EXEC) examples/basic/checkbox$(EXEC) examples/basic/messagebox$(EXEC) examples/basic/viewport$(EXEC) examples/basic/listbox$(EXEC) examples/color_picker$(EXEC)
 
-ifeq ($(OPENGL),1)
-L_OBJS += src/widget/opengl.o
-
-EXAMPLES += examples/gldemos/clock$(EXEC) examples/gldemos/triangle$(EXEC) examples/gldemos/gears$(EXEC) examples/gldemos/boing$(EXEC) examples/gldemos/cube$(EXEC) examples/gldemos/tripaint$(EXEC)
-endif
-
-ifeq ($(VULKAN),1)
-L_OBJS += src/widget/vulkan.o
-EXAMPLES += examples/vkdemos/vulkan$(EXEC)
-endif
-
 .PHONY: all install format clean lib examples
 
 all: lib examples
diff --git a/mk/flags.mk b/mk/flags.mk
new file mode 100644
index 0000000..0b90061
--- /dev/null
+++ b/mk/flags.mk
@@ -0,0 +1,42 @@
+# $Id$
+
+# Standard gcc accepts this but we have to override this for Apple's gcc.
+SHARED = -shared
+
+ifeq ($(UNIX),1)
+L_CFLAGS += -DUSE_X11 -DUNIX
+L_OBJS += src/backend/x11.o
+L_LIBS += -lm -lX11 -lXrender -lXcursor
+
+GL = -lGL -lGLU
+
+E_LIBS += -lm
+
+LIB = lib
+SO = .so
+EXEC =
+endif
+
+ifeq ($(WINDOWS),1)
+L_CFLAGS += -DUSE_GDI
+L_LDFLAGS += -Wl,--out-implib,src/libMw.a -static-libgcc
+L_OBJS += src/backend/gdi.o
+L_LIBS += -lgdi32
+
+GL = -lopengl32 -lglu32
+
+LIB =
+SO = .dll
+EXEC = .exe
+endif
+
+ifeq ($(DARWIN),1)
+L_CFLAGS += -DSTBI_NO_THREAD_LOCALS -DUSE_DARWIN
+L_OBJS += src/backend/mac/mac.o src/backend/mac/carbon.o
+
+LIB = lib
+SO = .dylib
+EXEC =
+
+SHARED = -dynamiclib
+endif
diff --git a/mk/freetype2.mk b/mk/freetype2.mk
new file mode 100644
index 0000000..8f96253
--- /dev/null
+++ b/mk/freetype2.mk
@@ -0,0 +1,10 @@
+# $Id$
+
+ifeq ($(USE_FREETYPE2),1)
+L_CFLAGS += -DUSE_FREETYPE2
+
+ifneq ($(CROSS),1)
+L_CFLAGS += $(shell pkg-config --cflags freetype2)
+L_LIBS += $(shell pkg-config --libs freetype2)
+endif
+endif
diff --git a/mk/opengl.mk b/mk/opengl.mk
new file mode 100644
index 0000000..bf9e597
--- /dev/null
+++ b/mk/opengl.mk
@@ -0,0 +1,7 @@
+# $Id$
+
+ifeq ($(OPENGL),1)
+L_OBJS += src/widget/opengl.o
+
+EXAMPLES += examples/gldemos/clock$(EXEC) examples/gldemos/triangle$(EXEC) examples/gldemos/gears$(EXEC) examples/gldemos/boing$(EXEC) examples/gldemos/cube$(EXEC) examples/gldemos/tripaint$(EXEC)
+endif
diff --git a/mk/platform.mk b/mk/platform.mk
new file mode 100644
index 0000000..3bb4900
--- /dev/null
+++ b/mk/platform.mk
@@ -0,0 +1,53 @@
+# $Id$
+
+ifeq ($(TARGET),)
+TARGET = $(shell uname -s)
+endif
+ifneq ($(TARGET),$(shell uname -s))
+CROSS = 1
+endif
+
+FOUND_PLATFORM = 0
+
+ifeq ($(TARGET),NetBSD)
+CFLAGS += -I/usr/X11R7/include -I/usr/pkg/include
+LDFLAGS += -L/usr/X11R7/lib -L/usr/pkg/lib -Wl,-R/usr/X11R7/lib -Wl,-R/usr/pkg/lib
+UNIX = 1
+OPENGL = 1
+VULKAN = 1
+FOUND_PLATFORM = 1
+endif
+
+ifeq ($(TARGET),Linux)
+L_LIBS += -ldl
+UNIX = 1
+OPENGL = 1
+VULKAN = 1
+FOUND_PLATFORM = 1
+endif
+
+ifeq ($(TARGET),Windows)
+WINDOWS = 1
+OPENGL = 1
+VULKAN = 1
+FOUND_PLATFORM = 1
+endif
+
+ifeq ($(TARGET),SunOS)
+CC = gcc
+UNIX = 1
+L_LIBS += -lsocket -lnsl
+OPENGL = 1
+FOUND_PLATFORM = 1
+endif
+
+ifeq ($(TARGET),Darwin)
+CC = gcc
+DARWIN = 1
+L_LIBS += -framework Carbon
+FOUND_PLATFORM = 1
+endif
+
+ifeq ($(FOUND_PLATFORM),0)
+$(error Add your platform definition)
+endif
diff --git a/mk/stb.mk b/mk/stb.mk
new file mode 100644
index 0000000..4e85f4f
--- /dev/null
+++ b/mk/stb.mk
@@ -0,0 +1,11 @@
+# $Id$
+
+ifeq ($(USE_STB_IMAGE),1)
+L_CFLAGS += -DUSE_STB_IMAGE
+else
+include external/deps.mk
+endif
+
+ifeq ($(USE_STB_TRUETYPE),1)
+L_CFLAGS += -DUSE_STB_TRUETYPE
+endif
diff --git a/mk/vulkan.mk b/mk/vulkan.mk
new file mode 100644
index 0000000..0a99138
--- /dev/null
+++ b/mk/vulkan.mk
@@ -0,0 +1,17 @@
+# $Id$
+
+ifeq ($(TARGET),NetBSD)
+VULKAN_NO_STRING_HELPER = 1
+endif
+
+ifeq ($(VULKAN_NO_STRING_HELPER),1)
+VK_STRING_HELPER_DEFINE =
+else
+VK_STRING_HELPER_DEFINE = -DHAS_VK_ENUM_STRING_HELPER
+endif
+CFLAGS += $(VK_STRING_HELPER_DEFINE)
+
+ifeq ($(VULKAN),1)
+L_OBJS += src/widget/vulkan.o
+EXAMPLES += examples/vkdemos/vulkan$(EXEC)
+endif