diff --git a/.gitignore b/.gitignore
index b0ad30c..759a4aa 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,5 @@
 /*.bin
 /*.hex
 *.d
+downloads/
+tools/
diff --git a/make/system-id.mk b/make/system-id.mk
new file mode 100644
index 0000000..1fd42ed
--- /dev/null
+++ b/make/system-id.mk
@@ -0,0 +1,46 @@
+# shared.mk
+#
+# environment variables common to all operating systems supported by the make system
+
+# Make sure we know a few things about the architecture
+UNAME := $(shell uname)
+ARCH := $(shell uname -m)
+ifneq (,$(filter $(ARCH), x86_64 amd64))
+  X86-64 := 1
+  X86_64 := 1
+  AMD64 := 1
+  ARCHFAMILY := x86_64
+else
+  ARCHFAMILY := $(ARCH)
+endif
+
+# configure some variables dependent upon what type of system this is
+
+# Linux
+ifeq ($(UNAME), Linux)
+  OSFAMILY := linux
+endif
+
+# Mac OSX
+ifeq ($(UNAME), Darwin)
+  OSFAMILY := macosx
+endif
+
+# Windows using MinGW shell
+ifeq (MINGW, $(findstring MINGW,$(UNAME)))
+  OSFAMILY := windows
+  MINGW := 1
+endif
+
+# Windows using Cygwin shell
+ifeq (CYGWIN ,$(findstring CYGWIN,$(UNAME)))
+  OSFAMILY := windows
+  CYGWIN := 1
+endif
+
+# report an error if we couldn't work out what OS this is running on
+ifndef OSFAMILY
+  $(info uname reports $(UNAME))
+  $(info uname -m reports $(ARCH))
+  $(error failed to detect operating system)
+endif
diff --git a/make/tools.mk b/make/tools.mk
new file mode 100644
index 0000000..7b65029
--- /dev/null
+++ b/make/tools.mk
@@ -0,0 +1,319 @@
+###############################################################
+#
+# Installers for tools
+#
+# NOTE: These are not tied to the default goals
+#       and must be invoked manually
+#
+###############################################################
+
+##############################
+#
+# Check that environmental variables are sane
+#
+##############################
+
+# Set up ARM (STM32) SDK
+ARM_SDK_DIR ?= $(TOOLS_DIR)/gcc-arm-none-eabi-9-2020-q2-update
+# Checked below, Should match the output of $(shell arm-none-eabi-gcc -dumpversion)
+GCC_REQUIRED_VERSION ?= 9.3.1
+
+.PHONY: arm_sdk_version
+
+arm_sdk_version:
+	$(V1) $(ARM_SDK_PREFIX)gcc --version
+
+## arm_sdk_install   : Install Arm SDK
+.PHONY: arm_sdk_install
+
+ARM_SDK_URL_BASE  := https://developer.arm.com/-/media/Files/downloads/gnu-rm/9-2020q2/gcc-arm-none-eabi-9-2020-q2-update
+
+# source: https://developer.arm.com/open-source/gnu-toolchain/gnu-rm/downloads
+ifeq ($(OSFAMILY), linux)
+  ARM_SDK_URL  := $(ARM_SDK_URL_BASE)-x86_64-linux.tar.bz2
+endif
+
+ifeq ($(OSFAMILY), macosx)
+  ARM_SDK_URL  := $(ARM_SDK_URL_BASE)-mac.tar.bz2
+endif
+
+ifeq ($(OSFAMILY), windows)
+  ARM_SDK_URL  := $(ARM_SDK_URL_BASE)-win32.zip
+endif
+
+ARM_SDK_FILE := $(notdir $(ARM_SDK_URL))
+
+SDK_INSTALL_MARKER := $(ARM_SDK_DIR)/bin/arm-none-eabi-gcc-$(GCC_REQUIRED_VERSION)
+
+# order-only prereq on directory existance:
+arm_sdk_install: | $(TOOLS_DIR)
+
+arm_sdk_install: arm_sdk_download $(SDK_INSTALL_MARKER)
+
+$(SDK_INSTALL_MARKER):
+ifneq ($(OSFAMILY), windows)
+        # binary only release so just extract it
+	$(V1) tar -C $(TOOLS_DIR) -xjf "$(DL_DIR)/$(ARM_SDK_FILE)"
+else
+	$(V1) unzip -q -d $(ARM_SDK_DIR) "$(DL_DIR)/$(ARM_SDK_FILE)"
+endif
+
+.PHONY: arm_sdk_download
+arm_sdk_download: | $(DL_DIR)
+arm_sdk_download: $(DL_DIR)/$(ARM_SDK_FILE)
+$(DL_DIR)/$(ARM_SDK_FILE):
+        # download the source only if it's newer than what we already have
+	$(V1) curl -L -k -o "$(DL_DIR)/$(ARM_SDK_FILE)" -z "$(DL_DIR)/$(ARM_SDK_FILE)" "$(ARM_SDK_URL)"
+
+
+## arm_sdk_clean     : Uninstall Arm SDK
+.PHONY: arm_sdk_clean
+arm_sdk_clean:
+	$(V1) [ ! -d "$(ARM_SDK_DIR)" ] || $(RM) -r $(ARM_SDK_DIR)
+	$(V1) [ ! -d "$(DL_DIR)" ] || $(RM) -r $(DL_DIR)
+
+.PHONY: openocd_win_install
+
+openocd_win_install: | $(DL_DIR) $(TOOLS_DIR)
+openocd_win_install: OPENOCD_URL  := git://git.code.sf.net/p/openocd/code
+openocd_win_install: OPENOCD_REV  := cf1418e9a85013bbf8dbcc2d2e9985695993d9f4
+openocd_win_install: OPENOCD_OPTIONS :=
+
+ifeq ($(OPENOCD_FTDI), yes)
+openocd_win_install: OPENOCD_OPTIONS := $(OPENOCD_OPTIONS) --enable-ft2232_ftd2xx --with-ftd2xx-win32-zipdir=$(FTD2XX_DIR)
+endif
+
+openocd_win_install: openocd_win_clean libusb_win_install ftd2xx_install
+        # download the source
+	@echo " DOWNLOAD     $(OPENOCD_URL) @ $(OPENOCD_REV)"
+	$(V1) [ ! -d "$(OPENOCD_BUILD_DIR)" ] || $(RM) -rf "$(OPENOCD_BUILD_DIR)"
+	$(V1) mkdir -p "$(OPENOCD_BUILD_DIR)"
+	$(V1) git clone --no-checkout $(OPENOCD_URL) "$(DL_DIR)/openocd-build"
+	$(V1) ( \
+	  cd $(OPENOCD_BUILD_DIR) ; \
+	  git checkout -q $(OPENOCD_REV) ; \
+	)
+
+        # apply patches
+	@echo " PATCH        $(OPENOCD_BUILD_DIR)"
+	$(V1) ( \
+	  cd $(OPENOCD_BUILD_DIR) ; \
+	  git apply < $(ROOT_DIR)/flight/Project/OpenOCD/0003-freertos-cm4f-fpu-support.patch ; \
+	  git apply < $(ROOT_DIR)/flight/Project/OpenOCD/0004-st-icdi-disable.patch ; \
+	)
+
+        # build and install
+	@echo " BUILD        $(OPENOCD_WIN_DIR)"
+	$(V1) mkdir -p "$(OPENOCD_WIN_DIR)"
+	$(V1) ( \
+	  cd $(OPENOCD_BUILD_DIR) ; \
+	  ./bootstrap ; \
+	  ./configure --enable-maintainer-mode --prefix="$(OPENOCD_WIN_DIR)" \
+		--build=i686-pc-linux-gnu --host=i586-mingw32msvc \
+		CPPFLAGS=-I$(LIBUSB_WIN_DIR)/include \
+		LDFLAGS=-L$(LIBUSB_WIN_DIR)/lib/gcc \
+		$(OPENOCD_OPTIONS) \
+		--disable-werror \
+		--enable-stlink ; \
+	  $(MAKE) ; \
+	  $(MAKE) install ; \
+	)
+
+        # delete the extracted source when we're done
+	$(V1) [ ! -d "$(OPENOCD_BUILD_DIR)" ] || $(RM) -rf "$(OPENOCD_BUILD_DIR)"
+
+.PHONY: openocd_win_clean
+openocd_win_clean:
+	@echo " CLEAN        $(OPENOCD_WIN_DIR)"
+	$(V1) [ ! -d "$(OPENOCD_WIN_DIR)" ] || $(RM) -r "$(OPENOCD_WIN_DIR)"
+
+# Set up openocd tools
+OPENOCD_DIR       := $(TOOLS_DIR)/openocd
+OPENOCD_WIN_DIR   := $(TOOLS_DIR)/openocd_win
+OPENOCD_BUILD_DIR := $(DL_DIR)/openocd-build
+
+.PHONY: openocd_install
+
+openocd_install: | $(DL_DIR) $(TOOLS_DIR)
+openocd_install: OPENOCD_URL     := git://git.code.sf.net/p/openocd/code
+openocd_install: OPENOCD_TAG     := v0.9.0
+openocd_install: OPENOCD_OPTIONS := --enable-maintainer-mode --prefix="$(OPENOCD_DIR)" --enable-buspirate --enable-stlink
+
+ifeq ($(OPENOCD_FTDI), yes)
+openocd_install: OPENOCD_OPTIONS := $(OPENOCD_OPTIONS) --enable-ftdi
+endif
+
+ifeq ($(UNAME), Darwin)
+openocd_install: OPENOCD_OPTIONS := $(OPENOCD_OPTIONS) --disable-option-checking
+endif
+
+openocd_install: openocd_clean
+        # download the source
+	@echo " DOWNLOAD     $(OPENOCD_URL) @ $(OPENOCD_TAG)"
+	$(V1) [ ! -d "$(OPENOCD_BUILD_DIR)" ] || $(RM) -rf "$(OPENOCD_BUILD_DIR)"
+	$(V1) mkdir -p "$(OPENOCD_BUILD_DIR)"
+	$(V1) git clone --no-checkout $(OPENOCD_URL) "$(OPENOCD_BUILD_DIR)"
+	$(V1) ( \
+	  cd $(OPENOCD_BUILD_DIR) ; \
+	  git checkout -q tags/$(OPENOCD_TAG) ; \
+	)
+
+        # build and install
+	@echo " BUILD        $(OPENOCD_DIR)"
+	$(V1) mkdir -p "$(OPENOCD_DIR)"
+	$(V1) ( \
+	  cd $(OPENOCD_BUILD_DIR) ; \
+	  ./bootstrap ; \
+	  ./configure  $(OPENOCD_OPTIONS) ; \
+	  $(MAKE) ; \
+	  $(MAKE) install ; \
+	)
+
+        # delete the extracted source when we're done
+	$(V1) [ ! -d "$(OPENOCD_BUILD_DIR)" ] || $(RM) -rf "$(OPENOCD_BUILD_DIR)"
+
+.PHONY: openocd_clean
+openocd_clean:
+	@echo " CLEAN        $(OPENOCD_DIR)"
+	$(V1) [ ! -d "$(OPENOCD_DIR)" ] || $(RM) -r "$(OPENOCD_DIR)"
+
+STM32FLASH_DIR := $(TOOLS_DIR)/stm32flash
+
+.PHONY: stm32flash_install
+stm32flash_install: STM32FLASH_URL := http://stm32flash.googlecode.com/svn/trunk
+stm32flash_install: STM32FLASH_REV := 61
+stm32flash_install: stm32flash_clean
+        # download the source
+	@echo " DOWNLOAD     $(STM32FLASH_URL) @ r$(STM32FLASH_REV)"
+	$(V1) svn export -q -r "$(STM32FLASH_REV)" "$(STM32FLASH_URL)" "$(STM32FLASH_DIR)"
+
+        # build
+	@echo " BUILD        $(STM32FLASH_DIR)"
+	$(V1) $(MAKE) --silent -C $(STM32FLASH_DIR) all
+
+.PHONY: stm32flash_clean
+stm32flash_clean:
+	@echo " CLEAN        $(STM32FLASH_DIR)"
+	$(V1) [ ! -d "$(STM32FLASH_DIR)" ] || $(RM) -r "$(STM32FLASH_DIR)"
+
+# Set up uncrustify tools
+UNCRUSTIFY_DIR := $(TOOLS_DIR)/uncrustify-0.61
+UNCRUSTIFY_BUILD_DIR := $(DL_DIR)/uncrustify
+
+.PHONY: uncrustify_install
+uncrustify_install: | $(DL_DIR) $(TOOLS_DIR)
+uncrustify_install: UNCRUSTIFY_URL := http://downloads.sourceforge.net/project/uncrustify/uncrustify/uncrustify-0.61/uncrustify-0.61.tar.gz
+uncrustify_install: UNCRUSTIFY_FILE := uncrustify-0.61.tar.gz
+uncrustify_install: UNCRUSTIFY_OPTIONS := prefix=$(UNCRUSTIFY_DIR)
+uncrustify_install: uncrustify_clean
+ifneq ($(OSFAMILY), windows)
+	@echo " DOWNLOAD     $(UNCRUSTIFY_URL)"
+	$(V1) curl -L -k -o "$(DL_DIR)/$(UNCRUSTIFY_FILE)" "$(UNCRUSTIFY_URL)"
+endif
+        # extract the src
+	@echo " EXTRACT      $(UNCRUSTIFY_FILE)"
+	$(V1) tar -C $(TOOLS_DIR) -xf "$(DL_DIR)/$(UNCRUSTIFY_FILE)"
+
+	@echo " BUILD        $(UNCRUSTIFY_DIR)"
+	$(V1) ( \
+	  cd $(UNCRUSTIFY_DIR) ; \
+	  ./configure --prefix="$(UNCRUSTIFY_DIR)" ; \
+	  $(MAKE) ; \
+	  $(MAKE) install ; \
+	)
+	      # delete the extracted source when we're done
+	$(V1) [ ! -d "$(UNCRUSTIFY_BUILD_DIR)" ] || $(RM) -r "$(UNCRUSTIFY_BUILD_DIR)"
+
+.PHONY: uncrustify_clean
+uncrustify_clean:
+	@echo " CLEAN        $(UNCRUSTIFY_DIR)"
+	$(V1) [ ! -d "$(UNCRUSTIFY_DIR)" ] || $(RM) -r "$(UNCRUSTIFY_DIR)"
+	@echo " CLEAN        $(UNCRUSTIFY_BUILD_DIR)"
+	$(V1) [ ! -d "$(UNCRUSTIFY_BUILD_DIR)" ] || $(RM) -r "$(UNCRUSTIFY_BUILD_DIR)"
+
+# ZIP download URL
+zip_install: ZIP_URL  := http://pkgs.fedoraproject.org/repo/pkgs/zip/zip30.tar.gz/7b74551e63f8ee6aab6fbc86676c0d37/zip30.tar.gz
+
+zip_install: ZIP_FILE := $(notdir $(ZIP_URL))
+
+ZIP_DIR = $(TOOLS_DIR)/zip30
+
+# order-only prereq on directory existance:
+zip_install : | $(DL_DIR) $(TOOLS_DIR)
+zip_install: zip_clean
+	$(V1) curl -L -k -o "$(DL_DIR)/$(ZIP_FILE)" "$(ZIP_URL)"
+	$(V1) tar --force-local -C $(TOOLS_DIR) -xzf "$(DL_DIR)/$(ZIP_FILE)"
+ifneq ($(OSFAMILY), windows)
+	$(V1) cd "$(ZIP_DIR)" && $(MAKE) -f unix/Makefile generic_gcc
+else
+	$(V1) cd "$(ZIP_DIR)" && $(MAKE) -f win32/makefile.gcc
+endif
+
+.PHONY: zip_clean
+zip_clean:
+	$(V1) [ ! -d "$(ZIP_DIR)" ] || $(RM) -rf $(ZIP_DIR)
+
+##############################
+#
+# Set up paths to tools
+#
+##############################
+
+ifeq ($(shell [ -d "$(ARM_SDK_DIR)" ] && echo "exists"), exists)
+  ARM_SDK_PREFIX := $(ARM_SDK_DIR)/bin/arm-none-eabi-
+else ifeq (,$(findstring _install,$(MAKECMDGOALS)))
+  GCC_VERSION = $(shell arm-none-eabi-gcc -dumpversion)
+  ifeq ($(GCC_VERSION),)
+    $(error **ERROR** arm-none-eabi-gcc not in the PATH. Run 'make arm_sdk_install' to install automatically in the tools folder of this repo)
+  else ifneq ($(GCC_VERSION), $(GCC_REQUIRED_VERSION))
+    $(error **ERROR** your arm-none-eabi-gcc is '$(GCC_VERSION)', but '$(GCC_REQUIRED_VERSION)' is expected. Override with 'GCC_REQUIRED_VERSION' in make/local.mk or run 'make arm_sdk_install' to install the right version automatically in the tools folder of this repo)
+  endif
+
+  # ARM tookchain is in the path, and the version is what's required.
+  ARM_SDK_PREFIX ?= arm-none-eabi-
+endif
+
+ifeq ($(shell [ -d "$(ZIP_DIR)" ] && echo "exists"), exists)
+  export ZIPBIN := $(ZIP_DIR)/zip
+else
+  export ZIPBIN := zip
+endif
+
+ifeq ($(shell [ -d "$(OPENOCD_DIR)" ] && echo "exists"), exists)
+  OPENOCD := $(OPENOCD_DIR)/bin/openocd
+else
+  # not installed, hope it's in the path...
+  OPENOCD ?= openocd
+endif
+
+ifeq ($(shell [ -d "$(UNCRUSTIFY_DIR)" ] && echo "exists"), exists)
+  UNCRUSTIFY := $(UNCRUSTIFY_DIR)/bin/uncrustify
+else
+  # not installed, hope it's in the path...
+  UNCRUSTIFY ?= uncrustify
+endif
+
+# Google Breakpad
+DUMP_SYMBOLS_TOOL := $(TOOLS_DIR)/breakpad/$(OSFAMILY)-$(ARCHFAMILY)/dump_syms
+BREAKPAD_URL := http://dronin.tracer.nz/tools/breakpad.zip
+BREAKPAD_DL_FILE := $(DL_DIR)/$(notdir $(BREAKPAD_URL))
+BREAKPAD_DIR := $(TOOLS_DIR)/breakpad
+
+.PHONY: breakpad_install
+breakpad_install: | $(DL_DIR) $(TOOLS_DIR)
+breakpad_install: breakpad_clean
+	@echo " DOWNLOAD     $(BREAKPAD_URL)"
+	$(V1) $(V1) curl -L -k -z "$(BREAKPAD_DL_FILE)" -o "$(BREAKPAD_DL_FILE)" "$(BREAKPAD_URL)"
+	@echo " EXTRACT      $(notdir $(BREAKPAD_DL_FILE))"
+	$(V1) mkdir -p "$(BREAKPAD_DIR)"
+	$(V1) unzip -q -d $(BREAKPAD_DIR) "$(BREAKPAD_DL_FILE)"
+ifeq ($(OSFAMILY), windows)
+	$(V1) ln -s "$(TOOLS_DIR)/breakpad/$(OSFAMILY)-i686" "$(TOOLS_DIR)/breakpad/$(OSFAMILY)-x86_64"
+endif
+
+.PHONY: breakpad_clean
+breakpad_clean:
+	@echo " CLEAN        $(BREAKPAD_DIR)"
+	$(V1) [ ! -d "$(BREAKPAD_DIR)" ] || $(RM) -rf $(BREAKPAD_DIR)
+	@echo " CLEAN        $(BREAKPAD_DL_FILE)"
+	$(V1) $(RM) -f $(BREAKPAD_DL_FILE)
diff --git a/makefile b/makefile
index 0c54a2c..c88fad4 100644
--- a/makefile
+++ b/makefile
@@ -33,8 +33,6 @@ CFLAGS = $(MCU) $(VALUES) $(INCLUDES) -O2 -Wall -fdata-sections -ffunction-secti
 CFLAGS += -DUSE_$(TARGET)
 CFLAGS += -MMD -MP -MF $(@:%.bin=%.d)
 
-ARM_SDK_PREFIX ?= arm-none-eabi-
-
 # Targets by signal input pin:
 # PB4: iFlight
 # PA2: all others
@@ -43,6 +41,20 @@ TARGET_PREFIX := BOOTLOADER_
 
 VERSION := $(shell grep "#define BOOTLOADER_VERSION" Core/Src/main.c | awk '{print $$3}' )
 
+# Working directories
+ROOT := $(patsubst %/,%,$(dir $(lastword $(MAKEFILE_LIST))))
+
+# Build tools, so we all share the same versions
+# import macros common to all supported build systems
+include $(ROOT)/make/system-id.mk
+
+# configure some directories that are relative to wherever ROOT_DIR is located
+ifndef TOOLS_DIR
+TOOLS_DIR := $(ROOT)/tools
+endif
+BUILD_DIR := $(ROOT)/build
+DL_DIR := $(ROOT)/downloads
+
 .PHONY : clean all version
 all : $(TARGETS)
 clean :
@@ -57,3 +69,13 @@ $(TARGETS:%=$(TARGET_PREFIX)%.bin) : clean $(OBJ)
 	$(CC) $(CFLAGS) $(LDFLAGS) -o $(TARGET_PREFIX)$(TARGET)_$(VERSION).elf $(OBJ)
 	$(CP) -O binary $(TARGET_PREFIX)$(TARGET)_$(VERSION).elf $(TARGET_PREFIX)$(TARGET)_$(VERSION).bin
 	$(CP) $(TARGET_PREFIX)$(TARGET)_$(VERSION).elf -O ihex  $(TARGET_PREFIX)$(TARGET)_$(VERSION).hex
+
+# mkdirs
+$(DL_DIR):
+	mkdir -p $@
+
+$(TOOLS_DIR):
+	mkdir -p $@
+
+# include the tools makefile
+include $(ROOT)/make/tools.mk