diff --git a/Makefile b/Makefile
index 1d703d5..d3d1ef2 100644
--- a/Makefile
+++ b/Makefile
@@ -1,84 +1,85 @@
 # -Wno-deprecated-declarations shuts up Apple OSX clang
-FLAGS = -Wall -Wno-deprecated-declarations -D_POSIX_C_SOURCE=200112L -O3 -pthread -l crypto
+FLAGS = -Wall -Wno-deprecated-declarations -D_POSIX_C_SOURCE=200112L -O3 -pthread 
+LIBS = -lssl -lcrypto
 # leave out -l crypto if using sha256.c instead of openssl
 CC = cc -std=c99 $(FLAGS)
 GPP = g++ -std=c++11 -DATOMIC $(FLAGS)
 # leave out -std=c++11 -DATOMIC for older GCC versions lacking c++11 support
 
 cuckoo4:	cuckoo.h cuckoo_miner.h simple_miner.cpp Makefile
-	$(GPP) -o cuckoo4 -DSHOW -DIDXSHIFT=0 -DPROOFSIZE=6 -DSIZESHIFT=4 simple_miner.cpp
+	$(GPP) -o cuckoo4 -DSHOW -DIDXSHIFT=0 -DPROOFSIZE=6 -DSIZESHIFT=4 simple_miner.cpp $(LIBS)
 
 cuckoo:		cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo -g -DSHOW -DLOGNBUCKETS=0 -DIDXSHIFT=0 -DPROOFSIZE=6 -DSIZESHIFT=4 cuckoo_miner.cpp
+	$(GPP) -o cuckoo -g -DSHOW -DLOGNBUCKETS=0 -DIDXSHIFT=0 -DPROOFSIZE=6 -DSIZESHIFT=4 cuckoo_miner.cpp $(LIBS)
 
 example:	cuckoo4
 	./cuckoo4 -e 66 -h 39
 
 cuckoo10:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo10 -DSIZESHIFT=10 cuckoo_miner.cpp
+	$(GPP) -o cuckoo10 -DSIZESHIFT=10 cuckoo_miner.cpp $(LIBS)
 
 cuckoo15:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo15 -DSIZESHIFT=15 cuckoo_miner.cpp
+	$(GPP) -o cuckoo15 -DSIZESHIFT=15 cuckoo_miner.cpp $(LIBS)
 
 cuckoo20:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo20 -DSIZESHIFT=20 cuckoo_miner.cpp
+	$(GPP) -o cuckoo20 -DSIZESHIFT=20 cuckoo_miner.cpp $(LIBS)
 
 cuckoo20.1:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo20.1 -DPART_BITS=1 -DSIZESHIFT=20 cuckoo_miner.cpp
+	$(GPP) -o cuckoo20.1 -DPART_BITS=1 -DSIZESHIFT=20 cuckoo_miner.cpp $(LIBS)
 
 verify20:	cuckoo.h cuckoo.c Makefile
-	$(CC) -o verify20 -DSIZESHIFT=20 cuckoo.c
+	$(CC) -o verify20 -DSIZESHIFT=20 cuckoo.c $(LIBS)
 
 test:	cuckoo20 verify20 Makefile
 	./cuckoo20 -h 85 | tail -1 | ./verify20 -h 85
 
 cuckoo25:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo25 -DSIZESHIFT=25 cuckoo_miner.cpp
+	$(GPP) -o cuckoo25 -DSIZESHIFT=25 cuckoo_miner.cpp $(LIBS)
 
 cuckoo25.1:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo25.1 -DPART_BITS=1 -DSIZESHIFT=25 cuckoo_miner.cpp
+	$(GPP) -o cuckoo25.1 -DPART_BITS=1 -DSIZESHIFT=25 cuckoo_miner.cpp $(LIBS)
 
 cuckoo28:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo28 -DSIZESHIFT=28 cuckoo_miner.cpp
+	$(GPP) -o cuckoo28 -DSIZESHIFT=28 cuckoo_miner.cpp $(LIBS)
 
 cuckoo28.1:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo28.1 -DPART_BITS=1 -DSIZESHIFT=28 cuckoo_miner.cpp
+	$(GPP) -o cuckoo28.1 -DPART_BITS=1 -DSIZESHIFT=28 cuckoo_miner.cpp $(LIBS)
 
 speedup:	cuckoo28 Makefile
 	for i in {1..4}; do echo $$i; (time for j in {0..6}; do ./cuckoo28 -t $$i -h $$j; done) 2>&1; done > speedup
 
 cuckoo30:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo30 -DSIZESHIFT=30 cuckoo_miner.cpp
+	$(GPP) -o cuckoo30 -DSIZESHIFT=30 cuckoo_miner.cpp $(LIBS)
 
 cuckoo30.1:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo30.1 -DPART_BITS=1 -DSIZESHIFT=30 cuckoo_miner.cpp
+	$(GPP) -o cuckoo30.1 -DPART_BITS=1 -DSIZESHIFT=30 cuckoo_miner.cpp $(LIBS)
 
 cuckoo30.2:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo30.2 -DPART_BITS=2 -DSIZESHIFT=30 cuckoo_miner.cpp
+	$(GPP) -o cuckoo30.2 -DPART_BITS=2 -DSIZESHIFT=30 cuckoo_miner.cpp $(LIBS)
 
 cuckoo30.3:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo30.3 -DPART_BITS=3 -DSIZESHIFT=30 cuckoo_miner.cpp
+	$(GPP) -o cuckoo30.3 -DPART_BITS=3 -DSIZESHIFT=30 cuckoo_miner.cpp $(LIBS)
 
 speedup30:	cuckoo30 Makefile
 	for i in {1..4}; do echo $$i; (time for j in {0..9}; do ./cuckoo30 -t $$i -h $$j; done) 2>&1; done > speedup30
 
 bounty28:	cuckoo.h bounty_miner.h bounty_miner.cpp Makefile
-	$(GPP) -o bounty28 -DSIZESHIFT=28 bounty_miner.cpp
+	$(GPP) -o bounty28 -DSIZESHIFT=28 bounty_miner.cpp $(LIBS)
 
 bounty30:	cuckoo.h bounty_miner.h bounty_miner.cpp Makefile
-	$(GPP) -o bounty30 -DSIZESHIFT=30 bounty_miner.cpp
+	$(GPP) -o bounty30 -DSIZESHIFT=30 bounty_miner.cpp $(LIBS)
 
 bounty32:	cuckoo.h bounty_miner.h bounty_miner.cpp Makefile
-	$(GPP) -o bounty32 -DSIZESHIFT=32 bounty_miner.cpp
+	$(GPP) -o bounty32 -DSIZESHIFT=32 bounty_miner.cpp $(LIBS)
 
 cuda28:	cuda_miner.cu Makefile
-	nvcc -o cuda28 -DSIZESHIFT=28 -arch sm_20 cuda_miner.cu -lcrypto
+	nvcc -o cuda28 -DSIZESHIFT=28 -arch sm_20 cuda_miner.cu -lssl -lcrypto 
 
 cuda30:	cuda_miner.cu Makefile
-	nvcc -o cuda30 -DSIZESHIFT=30 -arch sm_20 cuda_miner.cu -lcrypto
+	nvcc -o cuda30 -DSIZESHIFT=30 -arch sm_20 cuda_miner.cu -lssl -lcrypto
 
 cuda32:	cuda_miner.cu Makefile
-	nvcc -o cuda32 -DSIZESHIFT=32 -arch sm_20 cuda_miner.cu -lcrypto
+	nvcc -o cuda32 -DSIZESHIFT=32 -arch sm_20 cuda_miner.cu -lssl -lcrypto
 
 cpubounty:	cuckoo28 bounty28 cuckoo30 bounty30 cuckoo32 bounty32 Makefile
 	for c in 28 30 32; do for t in 1 2 4 8; do time for h in {0..9}; do ./cuckoo$$c -t $$t -h $$h; done; time for h in {0..9}; do ./bounty$$c -t $$t -h $$h; done;done; done
@@ -96,16 +97,16 @@ speedup30.3:	cuckoo30.3 Makefile
 	for i in {1..4}; do echo $$i; (time for j in {0..9}; do ./cuckoo30.3 -t $$i -h $$j; done) 2>&1; done > speedup30.3
 
 cuckoo32:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo32 -DSIZESHIFT=32 cuckoo_miner.cpp
+	$(GPP) -o cuckoo32 -DSIZESHIFT=32 cuckoo_miner.cpp $(LIBS)
 
 cuckoo32.1:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo32.1 -DPART_BITS=1 -DSIZESHIFT=32 cuckoo_miner.cpp
+	$(GPP) -o cuckoo32.1 -DPART_BITS=1 -DSIZESHIFT=32 cuckoo_miner.cpp $(LIBS)
 
 cuckoo32.2:	cuckoo.h cuckoo_miner.h cuckoo_miner.cpp Makefile
-	$(GPP) -o cuckoo32.2 -DPART_BITS=2 -DSIZESHIFT=32 cuckoo_miner.cpp
+	$(GPP) -o cuckoo32.2 -DPART_BITS=2 -DSIZESHIFT=32 cuckoo_miner.cpp $(LIBS)
 
 verify32:	cuckoo.h cuckoo.c Makefile
-	$(CC) -o verify32 -DSIZESHIFT=32 cuckoo.c
+	$(CC) -o verify32 -DSIZESHIFT=32 cuckoo.c $(LIBS)
 
 Cuckoo.class:	Cuckoo.java Makefile
 	javac -O Cuckoo.java
@@ -117,7 +118,7 @@ java:	Cuckoo.class SimpleMiner.class Makefile
 	java SimpleMiner -h 85 | tail -1 | java Cuckoo -h 85
 
 cuda:	cuda_miner.cu Makefile
-	nvcc -o cuda -DSIZESHIFT=14 -arch sm_20 cuda_miner.cu -lcrypto
+	nvcc -o cuda -DSIZESHIFT=14 -arch sm_20 cuda_miner.cu -lssl -lcrypto
 
 runcuda:	cuda
 	./cuda -h header
diff --git a/cuckoo.h b/cuckoo.h
index b99195d..3f04429 100644
--- a/cuckoo.h
+++ b/cuckoo.h
@@ -36,6 +36,17 @@ typedef struct {
    ((u64)((p)[2]) << 16) | ((u64)((p)[3]) << 24) | \
    ((u64)((p)[4]) << 32) | ((u64)((p)[5]) << 40) | \
    ((u64)((p)[6]) << 48) | ((u64)((p)[7]) << 56))
+
+#ifndef SHA256
+#define SHA256(d, n, md) do { \
+    SHA256_CTX c; \
+    SHA256_Init(&c); \
+    SHA256_Update(&c, d, n); \
+    SHA256_Final(md, &c); \
+  } while (0)
+#endif
+
+
  
 // derive siphash key from header
 void setheader(siphash_ctx *ctx, const char *header) {