diff --git a/example/Makefile b/example/Makefile
index bd48842..a0e4944 100644
--- a/example/Makefile
+++ b/example/Makefile
@@ -1,6 +1,6 @@
 
 CC = clang++
-CFLAGS = -std=c++14 -I.. -Wall -Wextra
+CFLAGS = -std=c++14 -I.. -Wall -Wextra -lpthread
 #OPENSSL_SUPPORT = -DCPPHTTPLIB_OPENSSL_SUPPORT -I/usr/local/opt/openssl/include -L/usr/local/opt/openssl/lib -lssl -lcrypto
 
 all: server client hello simplesvr benchmark
diff --git a/test/Makefile b/test/Makefile
index d802397..f466617 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -1,6 +1,6 @@
 
 CC = clang++
-CFLAGS = -std=c++11 -DGTEST_USE_OWN_TR1_TUPLE -I.. -I. -Wall -Wextra
+CFLAGS = -std=c++11 -DGTEST_USE_OWN_TR1_TUPLE -I.. -I. -Wall -Wextra -lpthread
 #OPENSSL_SUPPORT = -DCPPHTTPLIB_OPENSSL_SUPPORT -I/usr/local/opt/openssl/include -L/usr/local/opt/openssl/lib -lssl -lcrypto
 
 all : test