diff --git a/vowpalwabbit/serialization/src/autofb.cc b/vowpalwabbit/serialization/src/autofb.cc
index 921328d4ba4..61065b533cc 100644
--- a/vowpalwabbit/serialization/src/autofb.cc
+++ b/vowpalwabbit/serialization/src/autofb.cc
@@ -18,6 +18,7 @@ namespace autofb
     { typeid(std::int8_t), "int8" },
     { typeid(std::int16_t), "int16" },
     { typeid(std::int32_t), "int32" },
+    { typeid(std::int64_t), "int64" },
     { typeid(std::uint8_t), "uint8" },
     { typeid(std::uint16_t), "uint16" },
     { typeid(std::uint32_t), "uint32" },