diff --git a/DMR2NXDN/Makefile b/DMR2NXDN/Makefile
index 26301ec..deb1cc7 100644
--- a/DMR2NXDN/Makefile
+++ b/DMR2NXDN/Makefile
@@ -1,8 +1,8 @@
-CC      = gcc
-CXX     = g++
-CFLAGS  = -g -O3 -Wall -std=c++0x -pthread
+CC      ?= gcc
+CXX     ?= g++
+CFLAGS  ?= -g -O3 -Wall -std=c++0x -pthread
 LIBS    = -lm -lpthread
-LDFLAGS = -g
+LDFLAGS ?= -g
 
 OBJECTS = 	BPTC19696.o Conf.o CRC.o DMRData.o DMREMB.o DMREmbeddedData.o \
 			DMRFullLC.o DMRLC.o DMRLookup.o DMR2NXDN.o DMRSlotType.o  Golay2087.o \
diff --git a/DMR2YSF/Makefile b/DMR2YSF/Makefile
index 48c3687..c31d7c3 100644
--- a/DMR2YSF/Makefile
+++ b/DMR2YSF/Makefile
@@ -1,8 +1,8 @@
-CC      = gcc
-CXX     = g++
-CFLAGS  = -g -O3 -Wall -std=c++0x -pthread
+CC      ?= gcc
+CXX     ?= g++
+CFLAGS  ?= -g -O3 -Wall -std=c++0x -pthread
 LIBS    = -lm -lpthread
-LDFLAGS = -g
+LDFLAGS ?= -g
 
 OBJECTS = 	BPTC19696.o Conf.o CRC.o DelayBuffer.cpp DMRLookup.o DMREMB.o DMREmbeddedData.o \
 			DMR2YSF.o DMRFullLC.o MMDVMNetwork.o DMRLC.o DMRSlotType.o DMRData.o Golay2087.o \
diff --git a/NXDN2DMR/Makefile b/NXDN2DMR/Makefile
index 4829b0b..0a5633e 100644
--- a/NXDN2DMR/Makefile
+++ b/NXDN2DMR/Makefile
@@ -1,8 +1,8 @@
-CC      = gcc
-CXX     = g++
-CFLAGS  = -g -O3 -Wall -std=c++0x -pthread
+CC      ?= gcc
+CXX     ?= g++
+CFLAGS  ?= -g -O3 -Wall -std=c++0x -pthread
 LIBS    = -lm -lpthread
-LDFLAGS = -g
+LDFLAGS ?= -g
 
 OBJECTS = 	BPTC19696.o Conf.o CRC.o DelayBuffer.cpp DMRData.o DMREMB.o DMREmbeddedData.o \
 			DMRFullLC.o DMRLC.o DMRLookup.o DMRNetwork.o DMRSlotType.o  Golay2087.o \
diff --git a/YSF2DMR/Makefile b/YSF2DMR/Makefile
index b4a551a..4f26f06 100644
--- a/YSF2DMR/Makefile
+++ b/YSF2DMR/Makefile
@@ -1,8 +1,8 @@
-CC      = gcc
-CXX     = g++
-CFLAGS  = -g -O3 -Wall -std=c++0x -pthread
+CC      ?= gcc
+CXX     ?= g++
+CFLAGS  ?= -g -O3 -Wall -std=c++0x -pthread
 LIBS    = -lm -lpthread
-LDFLAGS = -g
+LDFLAGS ?= -g
 
 OBJECTS = 	BPTC19696.o Conf.o GPS.o TCPSocket.o DTMF.o APRSWriter.o APRSWriterThread.o CRC.o \
 			DelayBuffer.cpp DMRLookup.o DMREMB.o DMREmbeddedData.o APRSReader.o \
diff --git a/YSF2NXDN/Makefile b/YSF2NXDN/Makefile
index 95d972d..d4e62b8 100644
--- a/YSF2NXDN/Makefile
+++ b/YSF2NXDN/Makefile
@@ -1,8 +1,8 @@
-CC      = gcc
-CXX     = g++
-CFLAGS  = -g -O3 -Wall -std=c++0x -pthread
+CC      ?= gcc
+CXX     ?= g++
+CFLAGS  ?= -g -O3 -Wall -std=c++0x -pthread
 LIBS    = -lm -lpthread
-LDFLAGS = -g
+LDFLAGS ?= -g
 
 OBJECTS =   APRSReader.o APRSWriter.o APRSWriterThread.o Conf.o CRC.o DTMF.o Golay24128.o \
 			GPS.o Log.o ModeConv.o Mutex.o NXDNConvolution.o NXDNCRC.o NXDNLayer3.o NXDNLICH.o \
diff --git a/YSF2P25/Makefile b/YSF2P25/Makefile
index 908409e..72e9b98 100644
--- a/YSF2P25/Makefile
+++ b/YSF2P25/Makefile
@@ -1,8 +1,8 @@
-CC      = gcc
-CXX     = g++
-CFLAGS  = -g -O3 -Wall -std=c++0x -pthread
+CC      ?= gcc
+CXX     ?= g++
+CFLAGS  ?= -g -O3 -Wall -std=c++0x -pthread
 LIBS    = -lm -lpthread
-LDFLAGS = -g
+LDFLAGS ?= -g
 
 OBJECTS = 	Conf.o CRC.o DMRLookup.o DTMF.o Golay24128.o Hamming.o Log.o ModeConv.o Mutex.o \
 			P25Network.o StopWatch.o Sync.o Thread.o Timer.o UDPSocket.o Utils.o WiresX.o \