diff --git a/setupext.py b/setupext.py
index 006bb582af2..59110fd6d21 100644
--- a/setupext.py
+++ b/setupext.py
@@ -409,6 +409,12 @@ def finalize_options(self):
             self.include_dirs.append(numpy.get_include())
             self.include_dirs.append(ewah_bool_utils.get_include())
 
+            define_macros = [("NPY_NO_DEPRECATED_API", "NPY_1_7_API_VERSION")]
+            if self.define is None:
+                self.define = define_macros
+            else:
+                self.define.extend(define_macros)
+
         def build_extensions(self):
             self.check_extensions_list(self.extensions)