diff --git a/include/mapnik/symbolizer.hpp b/include/mapnik/symbolizer.hpp
index fd24e9d78..ea798e8b4 100644
--- a/include/mapnik/symbolizer.hpp
+++ b/include/mapnik/symbolizer.hpp
@@ -39,6 +39,7 @@
 #include <mapnik/raster_colorizer.hpp>
 // stl
 #include <type_traits>
+#include <algorithm>
 #include <memory>
 #include <vector>
 #include <string>
@@ -99,6 +100,12 @@ struct  MAPNIK_DECL symbolizer_base
     cont_type properties;
 };
 
+inline bool operator==(symbolizer_base const& lhs, symbolizer_base const& rhs)
+{
+    return lhs.properties.size() == rhs.properties.size() &&
+        std::equal(lhs.properties.begin(), lhs.properties.end(), rhs.properties.begin());
+}
+
 template <typename T>
 struct evaluate_path_wrapper
 {