IWYU
diff --git a/test/span_test.cpp b/test/span_test.cpp
index 08d7275..35ebd7b 100644
--- a/test/span_test.cpp
+++ b/test/span_test.cpp
@@ -5,6 +5,7 @@
 #include <rive/span.hpp>
 #include <catch.hpp>
 #include <cstdio>
+#include <vector>
 
 using namespace rive;