diff --git a/yacl/crypto/base/ecc/ec_point.h b/yacl/crypto/base/ecc/ec_point.h
index 855d783..b99077d 100644
--- a/yacl/crypto/base/ecc/ec_point.h
+++ b/yacl/crypto/base/ecc/ec_point.h
@@ -87,9 +87,6 @@ using Array160 =
 // a black box
 using EcPoint = std::variant<Array32, Array160, AnyPtr, AffinePoint>;
 
-}  // namespace yacl::crypto
+inline auto format_as(const AffinePoint &ap) { return fmt::streamed(ap); }
 
-namespace fmt {
-template <>
-struct formatter<yacl::crypto::AffinePoint> : ostream_formatter {};
-}  // namespace fmt
+}  // namespace yacl::crypto
diff --git a/yacl/link/transport/channel_chunked_base.cc b/yacl/link/transport/channel_chunked_base.cc
index baa449a..cc9db03 100644
--- a/yacl/link/transport/channel_chunked_base.cc
+++ b/yacl/link/transport/channel_chunked_base.cc
@@ -32,11 +32,6 @@ DECLARE_int32(h2_client_stream_window_size);
 
 }
 
-namespace fmt {
-template <>
-struct formatter<org::interconnection::link::TransType> : ostream_formatter {};
-}  // namespace fmt
-
 namespace yacl::link::transport {
 
 namespace ic = org::interconnection;
@@ -250,8 +245,8 @@ void ChannelChunkedBase::OnRequest(const ic_pb::PushRequest* request,
   } else {
     response->mutable_header()->set_error_code(ic::ErrorCode::INVALID_REQUEST);
     response->mutable_header()->set_error_msg(
-        fmt::format("unrecongnized trans type={}, from rank={}", trans_type,
-                    request->sender_rank()));
+        fmt::format("unrecongnized trans type={}, from rank={}",
+                    TransType_Name(trans_type), request->sender_rank()));
   }
 }
 
diff --git a/yacl/math/mpint/mp_int.h b/yacl/math/mpint/mp_int.h
index 3243d6f..d1ca419 100644
--- a/yacl/math/mpint/mp_int.h
+++ b/yacl/math/mpint/mp_int.h
@@ -369,6 +369,8 @@ class MPInt {
   friend class MontgomerySpace;
 };
 
+inline auto format_as(const MPInt &i) { return fmt::streamed(i); }
+
 }  // namespace yacl::math
 
 yacl::math::MPInt operator""_mp(const char *sz, size_t n);
@@ -400,8 +402,3 @@ MSGPACK_API_VERSION_NAMESPACE(MSGPACK_DEFAULT_API_NS) {
   }  // namespace adaptor
 }  // MSGPACK_API_VERSION_NAMESPACE(MSGPACK_DEFAULT_API_NS)
 }  // namespace msgpack
-
-namespace fmt {
-template <>
-struct formatter<yacl::math::MPInt> : ostream_formatter {};
-}  // namespace fmt