diff --git a/include/toml11/serializer.hpp b/include/toml11/serializer.hpp
index 318f763..a790613 100644
--- a/include/toml11/serializer.hpp
+++ b/include/toml11/serializer.hpp
@@ -1201,6 +1201,13 @@ std::string format(const std::vector<typename basic_value<TC>::key_type>& ks,
     return ser(ks, v);
 }
 
+template<typename TC>
+std::ostream& operator<<(std::ostream& os, const basic_value<TC>& v)
+{
+    os << format(v);
+    return os;
+}
+
 } // toml
 
 #if defined(TOML11_COMPILE_SOURCES)
diff --git a/tests/utility.hpp b/tests/utility.hpp
index a4df9b2..06c05e9 100644
--- a/tests/utility.hpp
+++ b/tests/utility.hpp
@@ -86,13 +86,6 @@ void toml11_test_parse_failure(F fn, std::string in, toml::detail::context<TC> c
 
 namespace toml
 {
-template<typename TC>
-std::ostream& operator<<(std::ostream& os, const toml::basic_value<TC>& v)
-{
-    os << toml::format(v);
-    return os;
-}
-
 std::ostream& operator<<(std::ostream& os, const integer_format_info&);
 std::ostream& operator<<(std::ostream& os, const floating_format_info&);
 std::ostream& operator<<(std::ostream& os, const string_format_info&);