diff --git a/Makefile b/Makefile
index 744b7bc6..4c98cfef 100644
--- a/Makefile
+++ b/Makefile
@@ -233,6 +233,7 @@ QUICKJS_SOURCES := \
 QUICKJS_OBJS := $(call get_objs,QUICKJS_SOURCES)
 $(QUICKJS_OBJS): CFLAGS += \
 	-DCONFIG_VERSION=\"$(shell cat deps/quickjs/VERSION)\" \
+	-DCONFIG_BIGNUM \
 	-DDUMP_LEAKS \
 	-D_GNU_SOURCE \
 	-Wno-sign-compare \