diff --git a/urandom_entropy_src.h b/urandom_entropy_src.h
index 44028c1..bf2f137 100644
--- a/urandom_entropy_src.h
+++ b/urandom_entropy_src.h
@@ -21,7 +21,7 @@ private:
 	std::mutex mtx;
 
 public:
-	auto event(accumulator::EventAdderImpl& adder) -> void;
+	auto event(accumulator::EventAdderImpl& adder) -> void override;
 
 	auto urandom_entropy_src_service() -> int;