diff --git a/engine.mk b/engine.mk
new file mode 100644
index 00000000..77151668
--- /dev/null
+++ b/engine.mk
@@ -0,0 +1,226 @@
+LOCAL_MAKEFILE:=$(MAKEFILE_LIST)
+
+ifeq ($(MAKECMDGOALS),spotless)
+spotless:
+	rm -rf build-*
+else
+
+ifndef LKROOT
+$(error please define LKROOT to the root of the lk build system)
+endif
+
+-include local.mk
+include make/macros.mk
+
+# If one of our goals (from the commandline) happens to have a
+# matching project/goal.mk, then we should re-invoke make with
+# that project name specified...
+
+project-name := $(firstword $(MAKECMDGOALS))
+
+ifneq ($(project-name),)
+ifneq ($(strip $(foreach d,$(LKINC),$(wildcard $(d)/project/$(project-name).mk))),)
+do-nothing := 1
+$(MAKECMDGOALS) _all: make-make
+make-make:
+	@PROJECT=$(project-name) $(MAKE) -rR -f $(LOCAL_MAKEFILE) $(filter-out $(project-name), $(MAKECMDGOALS))
+
+.PHONY: make-make
+endif
+endif
+
+ifeq ($(do-nothing),)
+
+ifeq ($(PROJECT),)
+$(error No project specified.  Use "make projectname" or put "PROJECT := projectname" in local.mk)
+endif
+
+DEBUG ?= 2
+
+BUILDROOT ?= .
+BUILDDIR := $(BUILDROOT)/build-$(PROJECT)
+OUTBIN := $(BUILDDIR)/lk.bin
+OUTELF := $(BUILDDIR)/lk.elf
+CONFIGHEADER := $(BUILDDIR)/config.h
+
+INCLUDES := -I$(BUILDDIR) -I$(LKROOT)/include $(addsuffix /include,$(addprefix -I,$(LKINC)))
+GLOBAL_OPTFLAGS ?= -Os
+GLOBAL_COMPILEFLAGS := -g -fno-builtin -finline -W -Wall -Wno-multichar -Wno-unused-parameter -Wno-unused-function -include $(CONFIGHEADER)
+GLOBAL_CFLAGS := --std=gnu99 -Werror-implicit-function-declaration
+#GLOBAL_CFLAGS += -Werror
+GLOBAL_CPPFLAGS := -fno-exceptions -fno-rtti -fno-threadsafe-statics
+#GLOBAL_CPPFLAGS += -Weffc++
+GLOBAL_ASMFLAGS := -DASSEMBLY
+GLOBAL_LDFLAGS :=
+
+GLOBAL_COMPILEFLAGS += -ffunction-sections -fdata-sections
+GLOBAL_LDFLAGS += --gc-sections
+
+# top level rule
+all:: $(OUTBIN) $(OUTELF).lst $(OUTELF).debug.lst $(OUTELF).sym $(OUTELF).size $(OUTELF).hex
+
+# master module object list
+ALLOBJS_MODULE :=
+
+# master object list (for dep generation)
+ALLOBJS :=
+
+# a linker script needs to be declared in one of the project/target/platform files
+LINKER_SCRIPT :=
+
+# anything you add here will be deleted in make clean
+GENERATED := $(CONFIGHEADER)
+
+# anything added to DEFINES will be put into $(BUILDDIR)/config.h
+DEFINES := LK=1
+
+# Anything added to SRCDEPS will become a dependency of every source file in the system.
+# Useful for header files that may be included by one or more source files.
+SRCDEPS := $(CONFIGHEADER)
+
+# these need to be filled out by the project/target/platform rules.mk files
+TARGET :=
+PLATFORM :=
+ARCH :=
+ALLMODULES :=
+
+# add any external module dependencies
+MODULES := $(EXTERNAL_MODULES)
+
+# any rules you put here will also be built by the system before considered being complete
+EXTRA_BUILDDEPS :=
+
+# any rules you put here will be depended on in clean builds
+EXTRA_CLEANDEPS :=
+
+# any objects you put here get linked with the final image
+EXTRA_OBJS :=
+
+# if someone defines this, the build id will be pulled into lib/version
+BUILDID ?=
+
+# try to include the project file
+-include project/$(PROJECT).mk
+ifndef TARGET
+$(error couldn't find project or project doesn't define target)
+endif
+include target/$(TARGET)/rules.mk
+ifndef PLATFORM
+$(error couldn't find target or target doesn't define platform)
+endif
+include platform/$(PLATFORM)/rules.mk
+
+$(info PROJECT = $(PROJECT))
+$(info PLATFORM = $(PLATFORM))
+$(info TARGET = $(TARGET))
+
+include arch/$(ARCH)/rules.mk
+include platform/rules.mk
+include target/rules.mk
+include kernel/rules.mk
+include dev/rules.mk
+include app/rules.mk
+
+# recursively include any modules in the MODULE variable, leaving a trail of included
+# modules in the ALLMODULES list
+include make/recurse.mk
+
+# any extra top level build dependencies that someone declared
+all:: $(EXTRA_BUILDDEPS)
+
+# add some automatic configuration defines
+DEFINES += \
+	PROJECT_$(PROJECT)=1 \
+	PROJECT=\"$(PROJECT)\" \
+	TARGET_$(TARGET)=1 \
+	TARGET=\"$(TARGET)\" \
+	PLATFORM_$(PLATFORM)=1 \
+	PLATFORM=\"$(PLATFORM)\" \
+	ARCH_$(ARCH)=1 \
+	ARCH=\"$(ARCH)\" \
+	$(addsuffix =1,$(addprefix WITH_,$(ALLMODULES)))
+
+# debug build?
+ifneq ($(DEBUG),)
+DEFINES += \
+	DEBUG=$(DEBUG)
+endif
+
+# allow additional defines from outside the build system
+ifneq ($(EXTERNAL_DEFINES),)
+DEFINES += $(EXTERNAL_DEFINES)
+$(info EXTERNAL_DEFINES = $(EXTERNAL_DEFINES))
+endif
+
+DEPS := $(ALLOBJS:%o=%d)
+
+#$(warning DEPS=$(DEPS))
+
+# default to no ccache
+CCACHE ?=
+CC := $(CCACHE) $(TOOLCHAIN_PREFIX)gcc
+LD := $(TOOLCHAIN_PREFIX)ld
+OBJDUMP := $(TOOLCHAIN_PREFIX)objdump
+OBJCOPY := $(TOOLCHAIN_PREFIX)objcopy
+CPPFILT := $(TOOLCHAIN_PREFIX)c++filt
+SIZE := $(TOOLCHAIN_PREFIX)size
+NM := $(TOOLCHAIN_PREFIX)nm
+
+# put all of the global build flags in config.h to force a rebuild if any change
+DEFINES += INCLUDES=\"$(subst $(SPACE),_,$(INCLUDES))\"
+DEFINES += GLOBAL_COMPILEFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_COMPILEFLAGS))\"
+DEFINES += GLOBAL_OPTFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_OPTFLAGS))\"
+DEFINES += GLOBAL_CFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_CFLAGS))\"
+DEFINES += GLOBAL_CPPFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_CPPFLAGS))\"
+DEFINES += GLOBAL_ASMFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_ASMFLAGS))\"
+DEFINES += GLOBAL_LDFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_LDFLAGS))\"
+
+# comment out or override if you want to see the full output of each command
+NOECHO ?= @
+
+#$(warning ALLMODULE_OBJS=$(ALLMODULE_OBJS))
+
+ifneq ($(OBJS),)
+$(warning OBJS=$(OBJS))
+$(error OBJS is not empty, please convert to new module format)
+endif
+ifneq ($(OPTFLAGS),)
+$(warning OPTFLAGS=$(OPTFLAGS))
+$(error OPTFLAGS is not empty, please use GLOBAL_OPTFLAGS or MODULE_OPTFLAGS)
+endif
+ifneq ($(CFLAGS),)
+$(warning CFLAGS=$(CFLAGS))
+$(error CFLAGS is not empty, please use GLOBAL_CFLAGS or MODULE_CFLAGS)
+endif
+ifneq ($(CPPFLAGS),)
+$(warning CPPFLAGS=$(CPPFLAGS))
+$(error CPPFLAGS is not empty, please use GLOBAL_CPPFLAGS or MODULE_CPPFLAGS)
+endif
+
+# the logic to compile and link stuff is in here
+include make/build.mk
+
+clean: $(EXTRA_CLEANDEPS)
+	rm -f $(ALLOBJS) $(DEPS) $(GENERATED) $(OUTBIN) $(OUTELF) $(OUTELF).lst $(OUTELF).debug.lst $(OUTELF).sym $(OUTELF).size $(OUTELF).hex
+
+install: all
+	scp $(OUTBIN) 192.168.0.4:/tftproot
+
+# generate a config.h file with all of the DEFINES laid out in #define format
+configheader:
+
+$(CONFIGHEADER): configheader
+	$(call MAKECONFIGHEADER,$@,DEFINES)
+
+# Empty rule for the .d files. The above rules will build .d files as a side
+# effect. Only works on gcc 3.x and above, however.
+%.d:
+
+ifeq ($(filter $(MAKECMDGOALS), clean), )
+-include $(DEPS)
+endif
+
+.PHONY: configheader
+endif
+
+endif # make spotless
diff --git a/make/build.mk b/make/build.mk
index 8cbae36c..fd4440f3 100644
--- a/make/build.mk
+++ b/make/build.mk
@@ -12,7 +12,7 @@ $(OUTELF).hex: $(OUTELF)
 
 $(OUTELF): $(ALLMODULE_OBJS) $(EXTRA_OBJS) $(LINKER_SCRIPT)
 	@echo linking $@
-	$(NOECHO)$(SIZE) -t $(ALLMODULE_OBJS)
+	$(NOECHO)$(SIZE) -t --common $(sort $(ALLMODULE_OBJS))
 	$(NOECHO)$(LD) $(GLOBAL_LDFLAGS) -T $(LINKER_SCRIPT) $(ALLMODULE_OBJS) $(EXTRA_OBJS) $(LIBGCC) -o $@
 
 $(OUTELF).sym: $(OUTELF)
diff --git a/make/macros.mk b/make/macros.mk
index e23715ea..a6bcc035 100644
--- a/make/macros.mk
+++ b/make/macros.mk
@@ -20,7 +20,7 @@ define MAKECONFIGHEADER
 	echo \#ifndef __$${LDEF}_H > $1.tmp; \
 	echo \#define __$${LDEF}_H >> $1.tmp; \
 	for d in `echo $($2) | tr '[:lower:]' '[:upper:]'`; do \
-		echo "#define $$d" | sed "s/=/\ /g;s/-/_/g;s/\//_/g" >> $1.tmp; \
+		echo "#define $$d" | sed "s/=/\ /g;s/-/_/g;s/\//_/g;s/\./_/g;s/\//_/g" >> $1.tmp; \
 	done; \
 	echo \#endif >> $1.tmp; \
 	if [ -f "$1" ]; then \
diff --git a/makefile b/makefile
index 2ff51ef4..bc38c848 100644
--- a/makefile
+++ b/makefile
@@ -1,201 +1,15 @@
-ifeq ($(MAKECMDGOALS),spotless)
-spotless:
-	rm -rf build-*
-else
+# the above include may override LKROOT and LKINC to allow external
+# directories to be included in the build
+-include lk_inc.mk
 
--include local.mk
-include make/macros.mk
+LKROOT ?= .
+LKINC ?=
 
-# If one of our goals (from the commandline) happens to have a
-# matching project/goal.mk, then we should re-invoke make with
-# that project name specified...
+LKINC := $(LKROOT) $(LKINC)
 
-project-name := $(firstword $(MAKECMDGOALS))
+# vaneer makefile that calls into the engine with lk as the build root
+# if we're the top level invocation, call ourselves with additional args
+$(MAKECMDGOALS) _top:
+	LKROOT=$(LKROOT) LKINC="$(LKINC)" $(MAKE) -rR -f $(LKROOT)/engine.mk $(addprefix -I,$(LKINC)) $(MAKECMDGOALS)
 
-ifneq ($(project-name),)
-ifneq ($(wildcard project/$(project-name).mk),)
-do-nothing := 1
-$(MAKECMDGOALS) _all: make-make
-make-make:
-	@PROJECT=$(project-name) $(MAKE) $(filter-out $(project-name), $(MAKECMDGOALS))
-endif
-endif
-
-ifeq ($(do-nothing),)
-
-ifeq ($(PROJECT),)
-$(error No project specified.  Use "make projectname" or put "PROJECT := projectname" in local.mk)
-endif
-
-DEBUG ?= 2
-
-BUILDDIR := build-$(PROJECT)
-OUTBIN := $(BUILDDIR)/lk.bin
-OUTELF := $(BUILDDIR)/lk
-CONFIGHEADER := $(BUILDDIR)/config.h
-
-INCLUDES := -I$(BUILDDIR) -Iinclude
-GLOBAL_OPTFLAGS ?= -Os
-GLOBAL_COMPILEFLAGS := -g -fno-builtin -finline -W -Wall -Wno-multichar -Wno-unused-parameter -Wno-unused-function -include $(CONFIGHEADER)
-GLOBAL_CFLAGS := --std=c99 -Werror-implicit-function-declaration
-#GLOBAL_CFLAGS += -Werror
-GLOBAL_CPPFLAGS := -fno-exceptions -fno-rtti -fno-threadsafe-statics
-#GLOBAL_CPPFLAGS += -Weffc++
-GLOBAL_ASMFLAGS := -DASSEMBLY
-GLOBAL_LDFLAGS :=
-
-GLOBAL_COMPILEFLAGS += -ffunction-sections -fdata-sections
-GLOBAL_LDFLAGS += -gc-sections
-
-# top level rule
-all:: $(OUTBIN) $(OUTELF).lst $(OUTELF).debug.lst $(OUTELF).sym $(OUTELF).size $(OUTELF).hex
-
-# master module object list
-ALLOBJS_MODULE :=
-
-# master object list (for dep generation)
-ALLOBJS :=
-
-# a linker script needs to be declared in one of the project/target/platform files
-LINKER_SCRIPT :=
-
-# anything you add here will be deleted in make clean
-GENERATED := $(CONFIGHEADER)
-
-# anything added to DEFINES will be put into $(BUILDDIR)/config.h
-DEFINES := LK=1
-
-# Anything added to SRCDEPS will become a dependency of every source file in the system.
-# Useful for header files that may be included by one or more source files.
-SRCDEPS := $(CONFIGHEADER)
-
-# these need to be filled out by the project/target/platform rules.mk files
-TARGET :=
-PLATFORM :=
-ARCH :=
-ALLMODULES :=
-MODULES :=
-
-# any rules you put here will also be built by the system before considered being complete
-EXTRA_BUILDDEPS :=
-
-# any rules you put here will be depended on in clean builds
-EXTRA_CLEANDEPS :=
-
-# any objects you put here get linked with the final image
-EXTRA_OBJS :=
-
-include project/$(PROJECT).mk
-include target/$(TARGET)/rules.mk
-include platform/$(PLATFORM)/rules.mk
-
-$(info PROJECT = $(PROJECT))
-$(info PLATFORM = $(PLATFORM))
-$(info TARGET = $(TARGET))
-
-include arch/$(ARCH)/rules.mk
-include platform/rules.mk
-include target/rules.mk
-include kernel/rules.mk
-include dev/rules.mk
-include app/rules.mk
-
-# recursively include any modules in the MODULE variable, leaving a trail of included
-# modules in the ALLMODULES list
-include make/recurse.mk
-
-# any extra top level build dependencies that someone declared
-all:: $(EXTRA_BUILDDEPS)
-
-# add some automatic configuration defines
-DEFINES += \
-	PROJECT_$(PROJECT)=1 \
-	TARGET_$(TARGET)=1 \
-	PLATFORM_$(PLATFORM)=1 \
-	ARCH_$(ARCH)=1 \
-	$(addsuffix =1,$(addprefix WITH_,$(ALLMODULES)))
-
-# debug build?
-ifneq ($(DEBUG),)
-DEFINES += \
-	DEBUG=$(DEBUG)
-endif
-
-# allow additional defines from outside the build system
-ifneq ($(EXTERNAL_DEFINES),)
-DEFINES += $(EXTERNAL_DEFINES)
-$(info EXTERNAL_DEFINES = $(EXTERNAL_DEFINES))
-endif
-
-DEPS := $(ALLOBJS:%o=%d)
-
-#$(warning DEPS=$(DEPS))
-
-# default to no ccache
-CCACHE ?= 
-CC := $(CCACHE) $(TOOLCHAIN_PREFIX)gcc
-LD := $(TOOLCHAIN_PREFIX)ld
-OBJDUMP := $(TOOLCHAIN_PREFIX)objdump
-OBJCOPY := $(TOOLCHAIN_PREFIX)objcopy
-CPPFILT := $(TOOLCHAIN_PREFIX)c++filt
-SIZE := $(TOOLCHAIN_PREFIX)size
-NM := $(TOOLCHAIN_PREFIX)nm
-
-# put all of the global build flags in config.h to force a rebuild if any change
-DEFINES += INCLUDES=\"$(subst $(SPACE),_,$(INCLUDES))\"
-DEFINES += GLOBAL_COMPILEFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_COMPILEFLAGS))\"
-DEFINES += GLOBAL_OPTFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_OPTFLAGS))\"
-DEFINES += GLOBAL_CFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_CFLAGS))\"
-DEFINES += GLOBAL_CPPFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_CPPFLAGS))\"
-DEFINES += GLOBAL_ASMFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_ASMFLAGS))\"
-DEFINES += GLOBAL_LDFLAGS=\"$(subst $(SPACE),_,$(GLOBAL_LDFLAGS))\"
-
-# comment out or override if you want to see the full output of each command
-NOECHO ?= @
-
-#$(warning ALLMODULE_OBJS=$(ALLMODULE_OBJS))
-
-ifneq ($(OBJS),)
-$(warning OBJS=$(OBJS))
-$(error OBJS is not empty, please convert to new module format)
-endif
-ifneq ($(OPTFLAGS),)
-$(warning OPTFLAGS=$(OPTFLAGS))
-$(error OPTFLAGS is not empty, please use GLOBAL_OPTFLAGS or MODULE_OPTFLAGS)
-endif
-ifneq ($(CFLAGS),)
-$(warning CFLAGS=$(CFLAGS))
-$(error CFLAGS is not empty, please use GLOBAL_CFLAGS or MODULE_CFLAGS)
-endif
-ifneq ($(CPPFLAGS),)
-$(warning CPPFLAGS=$(CPPFLAGS))
-$(error CPPFLAGS is not empty, please use GLOBAL_CPPFLAGS or MODULE_CPPFLAGS)
-endif
-
-# the logic to compile and link stuff is in here
-include make/build.mk
-
-clean: $(EXTRA_CLEANDEPS)
-	rm -f $(ALLOBJS) $(DEPS) $(GENERATED) $(OUTBIN) $(OUTELF) $(OUTELF).lst $(OUTELF).hex
-
-install: all
-	scp $(OUTBIN) 192.168.0.4:/tftproot
-
-# generate a config.h file with all of the DEFINES laid out in #define format
-configheader:
-
-$(CONFIGHEADER): configheader
-	$(call MAKECONFIGHEADER,$@,DEFINES)
-
-# Empty rule for the .d files. The above rules will build .d files as a side
-# effect. Only works on gcc 3.x and above, however.
-%.d:
-
-ifeq ($(filter $(MAKECMDGOALS), clean), )
--include $(DEPS)
-endif
-
-.PHONY: configheader
-endif
-
-endif # make spotless
+.PHONY: _top