diff --git a/Makefile b/Makefile
index f74932ccc..d2d4ca643 100644
--- a/Makefile
+++ b/Makefile
@@ -1,14 +1,5 @@
-# Hide full compilation line:
-ifneq ($(V),1)
-  Q?=@
-endif
-# To see full command lines, use make V=1
 
-CP = cp -a
-GZIP=gzip
-MKDIR = mkdir -p
-RM = rm -f
-RMDIR = rm -rf
+include Makefile.defs
 -include Makefile.platform
 -include .Makefile.options.cache
 include common_arm/Makefile.hal
diff --git a/Makefile.defs b/Makefile.defs
new file mode 100644
index 000000000..d69b58b33
--- /dev/null
+++ b/Makefile.defs
@@ -0,0 +1,42 @@
+# Hide full compilation line:
+ifneq ($(V),1)
+  Q?=@
+endif
+# To see full command lines, use make V=1
+
+# been here
+DEFSBEENHERE = true
+
+CP = cp -a
+GZIP = gzip
+MKDIR = mkdir -p
+RM = rm -f
+RMDIR = rm -rf
+MV = mv
+TOUCH = touch
+FALSE = false
+TAR = tar
+TARFLAGS ?= -v --ignore-failed-read -r
+TARFLAGS += -C .. -f
+CROSS  ?= arm-none-eabi-
+CC = gcc
+CXX = g++
+LD = g++
+
+PATHSEP=/
+PREFIX ?=             /usr/local
+INSTALLBINRELPATH =   /bin/
+INSTALLSHARERELPATH = /share/proxmark3/
+INSTALLFWRELPATH =    /share/proxmark3/firmware/
+INSTALLTOOLSRELPATH = /share/proxmark3/tools/
+
+platform = $(shell uname)
+DETECTED_OS=$(platform)
+
+ifeq ($(platform),Darwin)
+    AR= /usr/bin/ar rcs
+    RANLIB= /usr/bin/ranlib
+else
+    AR= ar rcs
+    RANLIB= ranlib
+endif
diff --git a/Makefile.host b/Makefile.host
index 861e697fb..8fb6fceed 100644
--- a/Makefile.host
+++ b/Makefile.host
@@ -1,36 +1,19 @@
-# Hide full compilation line:
-ifneq ($(V),1)
-  Q?=@
+# This Makefile might have been called from various subdirs, trying to find our Makefile.defs
+ifeq ($(DEFSBEENHERE),)
+    -include Makefile.defs
+endif
+ifeq ($(DEFSBEENHERE),)
+    -include ../Makefile.defs
+endif
+ifeq ($(DEFSBEENHERE),)
+    -include ../../Makefile.defs
+endif
+ifeq ($(DEFSBEENHERE),)
+    $(error Can't find Makefile.defs)
 endif
-# To see full command lines, use make V=1
-
-INSTALLBINRELPATH = /bin/
-INSTALLTOOLSRELPATH = /share/proxmark3/tools/
-
-CC = gcc
-LD = gcc
-RM = rm -f
-MV = mv
-CP = cp -a
-MKDIR = mkdir -p
-TOUCH = touch
-FALSE = false
 
 CFLAGS ?= -Wall -Werror -O3
 CFLAGS += $(MYDEFS) $(MYCFLAGS) $(MYINCLUDES)
-PREFIX ?= /usr/local
-
-platform = $(shell uname)
-
-ifeq ($(platform),Darwin)
-AR= /usr/bin/ar rcs
-RANLIB= /usr/bin/ranlib
-else
-AR= ar rcs
-RANLIB= ranlib
-endif
-RM= rm -f
-RMDIR= rm -rf
 
 vpath %.c $(MYSRCPATHS)
 
diff --git a/client/Makefile b/client/Makefile
index 5157e3e57..4c5d53c9c 100644
--- a/client/Makefile
+++ b/client/Makefile
@@ -9,34 +9,14 @@
 # Add -DNOFORCE  to disable the -F switch
 # Add -DPRESETS  to compile with preset models (edit config.h)
 
-# Hide full compilation line:
-ifneq ($(V),1)
-  Q?=@
-endif
-# To see full command lines, use make V=1
+# Must be called before any Makefile include
+ROOT_DIR:=$(dir $(realpath $(lastword $(MAKEFILE_LIST))))
+
+include ../Makefile.defs
 
-INSTALLBINRELPATH = /bin/
-INSTALLSHARERELPATH = /share/proxmark3/
 INSTALLBIN = proxmark3 proxmark3-flasher
 INSTALLSHARE = lualibs luascripts resources dictionaries
 
-CC = gcc
-CXX = g++
-LD = g++
-TAR = tar
-TARFLAGS ?= -v --ignore-failed-read -r
-TARFLAGS += -C .. -f
-RM = rm -f
-RMDIR= rm -rf
-MKDIR = mkdir -p
-MV = mv
-TOUCH = touch
-FALSE = false
-CP=cp -a
-
-platform = $(shell uname)
-ROOT_DIR:=$(dir $(realpath $(lastword $(MAKEFILE_LIST))))
-
 VPATH = ../common uart
 vpath %.dic dictionaries
 OBJDIR = obj
diff --git a/common_arm/Makefile.common b/common_arm/Makefile.common
index 5af77bcf7..52ec2ebd2 100644
--- a/common_arm/Makefile.common
+++ b/common_arm/Makefile.common
@@ -6,48 +6,34 @@
 # Common makefile functions for all platforms
 #-----------------------------------------------------------------------------
 
-# This new makefile replaces the previous Makefile/Makefile.linux
-# with as much common code for both environments as possible.
-# Following is a short OS detection to set up variables, all the
-# remaining Makefile should be portable and only depend on these
-# variables
-#
-
-ifneq ($(V),1)
-  Q?=@
-endif
-# To see full command lines, use make V=1
-
 # Make sure that all is the default target
 # (The including Makefile still needs to define what 'all' is)
 
 all:
 
-platform = $(shell uname)
-PREFIX?=/usr/local
-INSTALLFWRELPATH = /share/proxmark3/firmware/
+# This Makefile might have been called from various subdirs, trying to find our Makefile.defs
+ifeq ($(DEFSBEENHERE),)
+    -include Makefile.defs
+endif
+ifeq ($(DEFSBEENHERE),)
+    -include ../Makefile.defs
+endif
+ifeq ($(DEFSBEENHERE),)
+    -include ../../Makefile.defs
+endif
+ifeq ($(DEFSBEENHERE),)
+    $(error Can't find Makefile.defs)
+endif
 
-CROSS  ?= arm-none-eabi-
 CC = $(CROSS)gcc
 AS = $(CROSS)as
 LD = $(CROSS)ld
 OBJCOPY = $(CROSS)objcopy
-GZIP=gzip
-MV=mv
 
 OBJDIR = obj
 
 INCLUDE = -I../include -I../common_arm -I../common_fpga -I../common -I.
 
-TAR=tar
-TARFLAGS = -C .. -rvf
-RM=rm -f
-RMDIR=rm -rf
-CP=cp -a
-MKDIR=mkdir -p
-PATHSEP=/
-DETECTED_OS=$(platform)
-
 # Also search prerequisites in the common directory (for usb.c), the fpga directory (for fpga.bit), and the zlib directory
 VPATH = . ../common_arm ../common ../common/crapto1 ../common/mbedtls ../common/zlib ../fpga ../armsrc/Standalone