diff --git a/Makefile b/Makefile
index 74a4272..a7da80b 100644
--- a/Makefile
+++ b/Makefile
@@ -625,11 +625,12 @@
 51DEGREES_SRC =
 51DEGREES_INC = $(51DEGREES_SRC)
 51DEGREES_LIB = $(51DEGREES_SRC)
+OPTIONS_OBJS    += $(51DEGREES_LIB)/../cityhash/city.o
 OPTIONS_OBJS    += $(51DEGREES_LIB)/51Degrees.o
 OPTIONS_OBJS    += src/51d.o
-OPTIONS_CFLAGS  += -DUSE_51DEGREES $(if $(51DEGREES_INC),-I$(51DEGREES_INC))
+OPTIONS_CFLAGS  += -DUSE_51DEGREES -DFIFTYONEDEGREES_NO_THREADING $(if $(51DEGREES_INC),-I$(51DEGREES_INC))
 BUILD_OPTIONS   += $(call ignore_implicit,USE_51DEGREES)
-OPTIONS_LDFLAGS += $(if $(51DEGREES_LIB),-L$(51DEGREES_LIB)) -lz
+OPTIONS_LDFLAGS += $(if $(51DEGREES_LIB),-L$(51DEGREES_LIB)) -lm
 endif
 
 ifneq ($(USE_PCRE)$(USE_STATIC_PCRE)$(USE_PCRE_JIT),)