diff --git a/client/Makefile b/client/Makefile
index 490716eda..a1109a497 100644
--- a/client/Makefile
+++ b/client/Makefile
@@ -31,7 +31,12 @@ platform = $(shell uname)
 VPATH = ../common ../zlib ../uart
 OBJDIR = obj
 
-LDLIBS = -L/opt/local/lib -L/usr/local/lib -lreadline -lpthread -lm
+LDLIBS =
+ifneq ($(platform),Darwin)
+    LDLIBS += -L/opt/local/lib
+endif
+LDLIBS += -L/usr/local/lib -lreadline -lpthread -lm
+
 # RPi Zero gcc requires -latomic
 # but MacOSX /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld
 # doesn't recognize option --as-needed
diff --git a/client/jansson/Makefile b/client/jansson/Makefile
index 323d26216..1a60613d0 100644
--- a/client/jansson/Makefile
+++ b/client/jansson/Makefile
@@ -36,15 +36,26 @@ CFILES = $(filter %.c, $(libjansson_la_SOURCES))
 CMDOBJS = $(CFILES:%.c=%.o)
 CLEAN = $(CMDOBJS)
 
+platform = $(shell uname)
+
 CC= gcc
-CFLAGS= -O2 -Wall -Wno-unused-variable -Wno-unused-function -Wno-format-truncation
+CFLAGS= -O2 -Wall -Wno-unused-variable -Wno-unused-function
+ifneq ($(platform),Darwin)
+CFLAGS += -Wno-format-truncation
+endif
+
 LDFLAGS= $(SYSLDFLAGS) $(libjansson_la_LDFLAGS)
 LIBS= $(SYSLIBS) $(MYLIBS)
 DEFAULT_INCLUDES = -I.
 DEFS = -DHAVE_STDINT_H
 
+ifeq ($(platform),Darwin)
+AR= /usr/bin/ar rcs
+RANLIB= /usr/bin/ranlib
+else
 AR= ar rcs
 RANLIB= ranlib
+endif
 RM= rm -f
 TST= echo
 
diff --git a/client/tinycbor/Makefile b/client/tinycbor/Makefile
index 8124196eb..af22846e9 100644
--- a/client/tinycbor/Makefile
+++ b/client/tinycbor/Makefile
@@ -19,14 +19,21 @@ CFILES = $(filter %.c, $(tinycbor_SOURCES))
 CMDOBJS = $(CFILES:%.c=%.o)
 CLEAN = $(CMDOBJS)
 
+platform = $(shell uname)
+
 CC= gcc
 CFLAGS= -O2 -Wall -Wno-unused-variable -Wno-unused-function
 LIBS=  $(SYSLIBS) $(MYLIBS)
 DEFAULT_INCLUDES = -I. -I..
 DEFS = -DHAVE_STDINT_H
 
+ifeq ($(platform),Darwin)
+AR= /usr/bin/ar rcs
+RANLIB= /usr/bin/ranlib
+else
 AR= ar rcs
 RANLIB= ranlib
+endif
 RM= rm -f
 TST= echo
 
diff --git a/common/Makefile.common b/common/Makefile.common
index 132507547..2ab434562 100644
--- a/common/Makefile.common
+++ b/common/Makefile.common
@@ -43,15 +43,13 @@ TARFLAGS = -C .. -rvf
 #  amount of shell command line parsing going on. echo "" on 
 #  Windows yields literal "", on Linux yields an empty line
 ifeq ($(shell echo ""),)
-
-# This is probably a proper system, so we can use uname
-UNAME := $(shell uname)
 DELETE=rm -rf
 MOVE=mv
 COPY=cp
 PATHSEP=/
 FLASH_TOOL=client/flasher
-DETECTED_OS=$(UNAME)
+# This is probably a proper system, so we can use uname
+DETECTED_OS=$(platform)
 else
 
 # Assume that we are running on Windows.
diff --git a/common/mbedtls/Makefile b/common/mbedtls/Makefile
index fa0dff05f..a16b2cfd9 100644
--- a/common/mbedtls/Makefile
+++ b/common/mbedtls/Makefile
@@ -59,6 +59,8 @@ CFILES = $(filter %.c, $(mbedtls_SOURCES))
 CMDOBJS = $(CFILES:%.c=%.o)
 CLEAN = $(CMDOBJS)
 
+platform = $(shell uname)
+
 CC= gcc
 CFLAGS= -O2 -Wall -Wno-unused-variable -Wno-unused-function
 LDFLAGS= $(SYSLDFLAGS) $(mbedtls_LDFLAGS)
@@ -66,8 +68,13 @@ LIBS=  $(SYSLIBS) $(MYLIBS)
 DEFAULT_INCLUDES = -I. -I..
 DEFS = -DHAVE_STDINT_H
 
+ifeq ($(platform),Darwin)
+AR= /usr/bin/ar rcs
+RANLIB= /usr/bin/ranlib
+else
 AR= ar rcs
 RANLIB= ranlib
+endif
 RM= rm -f
 TST= echo
 
diff --git a/liblua/Makefile b/liblua/Makefile
index bf2a4fa3c..2b3d7614f 100644
--- a/liblua/Makefile
+++ b/liblua/Makefile
@@ -12,13 +12,20 @@ endif
 # Your platform. See PLATS for possible values.
 PLAT= none
 
+platform= $(shell uname)
+
 CC= gcc
 CFLAGS= -O3 -Wall -DLUA_COMPAT_ALL $(SYSCFLAGS) $(MYCFLAGS)
 LDFLAGS= $(SYSLDFLAGS) $(MYLDFLAGS)
 LIBS= -lm $(SYSLIBS) $(MYLIBS)
 
+ifeq ($(platform),Darwin)
+AR= /usr/bin/ar rc
+RANLIB= /usr/bin/ranlib
+else
 AR= ar rc
 RANLIB= ranlib
+endif
 RM= rm -f
 
 SYSCFLAGS=