diff --git a/build.sh b/build.sh
index f2ad9c9..ccf74e0 100644
--- a/build.sh
+++ b/build.sh
@@ -1,6 +1,7 @@
 g++ -shared -fPIC \
     -I/usr/include/python3.10 -I/usr/include/python3.10/numpy -I./include \
     -L./lib \
+    -DRTC_NUMPY_IMPL \
     rtc_plugins.cpp util/RTCContext.cpp \
     -lMRTCEngine -lboost_python310 -lpython3.10 \
     -Wl,-rpath='$ORIGIN/lib' \