title: Cross-Language Serialization Guide sidebar_position: 0 id: xlang_serialization_index license: | Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

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Apache Fory™ xlang (cross-language) serialization enables seamless data exchange between different programming languages. Serialize data in one language and deserialize it in another—without IDL definitions, schema compilation, or manual data conversion.

Features

  • No IDL Required: Serialize any object automatically without Protocol Buffers, Thrift, or other IDL definitions
  • Multi-Language Support: Java, Python, C++, Go, Rust, JavaScript all interoperate seamlessly
  • Reference Support: Shared and circular references work across language boundaries
  • Schema Evolution: Forward/backward compatibility when class definitions change
  • Zero-Copy: Out-of-band serialization for large binary data
  • High Performance: JIT compilation and optimized binary protocol

Supported Languages

LanguageStatusPackage
Java✅org.apache.fory:fory-core
Python✅pyfory
C++✅Bazel/CMake build
Go✅github.com/apache/fory/go/fory
Rust✅fory crate
JavaScript✅@apache-fory/fory

When to Use Xlang Mode

Use xlang mode when:

  • Building multi-language microservices
  • Creating polyglot data pipelines
  • Sharing data between frontend (JavaScript) and backend (Java/Python/Go)

Use language-native mode when:

  • All serialization/deserialization happens in the same language
  • Maximum performance is required (native mode is faster)
  • You need language-specific features (Python pickle compatibility, Java serialization hooks)

Quick Example

Java (Producer)

import org.apache.fory.*;
import org.apache.fory.config.*;

public class Person {
    public String name;
    public int age;
}

Fory fory = Fory.builder()
    .withLanguage(Language.XLANG)
    .build();
fory.register(Person.class, "example.Person");

Person person = new Person();
person.name = "Alice";
person.age = 30;
byte[] bytes = fory.serialize(person);
// Send bytes to Python, Go, Rust, etc.

Python (Consumer)

import pyfory
from dataclasses import dataclass

@dataclass
class Person:
    name: str
    age: pyfory.Int32Type

fory = pyfory.Fory()
fory.register_type(Person, typename="example.Person")

# Receive bytes from Java
person = fory.deserialize(bytes_from_java)
print(f"{person.name}, {person.age}")  # Alice, 30

Documentation

TopicDescription
Getting StartedInstallation and basic setup for all languages
Type MappingCross-language type mapping reference
SerializationBuilt-in types, custom types, reference handling
Zero-CopyOut-of-band serialization for large data
Row FormatCache-friendly binary format with random access
TroubleshootingCommon issues and solutions

Language-Specific Guides

For language-specific details and API reference:

Specifications