docs/guide/csharp/index.md

title: C# Serialization Guide sidebar_position: 0 id: 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

 http://www.apache.org/licenses/LICENSE-2.0

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Apache Fory™ C# is a high-performance, cross-language serialization library for .NET. It provides object graph serialization, schema evolution, generic object payload support, and a thread-safe wrapper for concurrent workloads.

Why Fory C#?

High performance binary serialization for .NET 8+
Xlang compatibility with Fory implementations in Java, Python, C++, Go, Rust, JavaScript/TypeScript, Swift, Dart, Scala, and Kotlin
Source-generator-based serializers for [ForyStruct] types, plus [ForyEnum] and [ForyUnion] registration
Optional reference tracking for shared and circular object graphs
Compatible mode for schema evolution
Thread-safe wrapper (ThreadSafeFory) for multi-threaded services

Quick Start

Requirements

.NET SDK 8.0+
C# language version 12+

Install from NuGet

Reference the single Apache.Fory package. It includes the Fory library and the source generator for [ForyStruct], [ForyEnum], and [ForyUnion] types.

<ItemGroup>
  <PackageReference Include="Apache.Fory" Version="1.3.0" />
</ItemGroup>

Basic Example

using Apache.Fory;

[ForyStruct]
public sealed class User
{
    public long Id { get; set; }
    public string Name { get; set; } = string.Empty;
    public string? Email { get; set; }
}

Fory fory = Fory.Builder().Build();
fory.Register<User>(1);

User user = new()
{
    Id = 1,
    Name = "Alice",
    Email = "alice@example.com",
};

byte[] payload = fory.Serialize(user);
User decoded = fory.Deserialize<User>(payload);

Core API Surface

Serialize<T>(in T value) / Deserialize<T>(...)
Serialize<object?>(...) / Deserialize<object?>(...) for dynamic payloads
Register<T>(uint typeId) and name registration APIs
Register<T, TSerializer>(...) for custom serializers

Documentation

Topic	Description
Configuration	Builder options and mode settings
Basic Serialization	Typed and dynamic serialization APIs
Xlang Serialization	Interoperability guidance
Schema Metadata	`[ForyField]` ids and schema type descriptors
Type Registration	Registering user types and custom serializers
Custom Serializers	Implementing `Serializer<T>`
References	Shared/circular reference handling
Schema Evolution	Compatible mode behavior
Supported Types	Built-in and generated type support
Thread Safety	`Fory` vs `ThreadSafeFory` usage
gRPC Support	Generated Fory-backed gRPC service companions
Troubleshooting	Common errors and debugging steps