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title: Introduction sidebar_position: 0 id: 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

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Binary Object Serialization reconstructs object graphs, including registered application types, collections, polymorphic values, and optional shared references.

Choose a mode

Mode	Use it when	Start here
Xlang (default)	Bytes cross runtime boundaries	Xlang Serialization
Native	Every writer and reader uses the same runtime family	Native serialization

Xlang and native are the only object-serialization modes. Row Format is a random-access analytical representation, and Fory JSON is a Java JSON codec; use the format chooser when object reconstruction is not your goal.

Read the concepts and modes

Read these pages before choosing a runtime API:

1. Core Concepts explains object graphs, types, schemas, references, polymorphism, and schema evolution across both modes.
2. Xlang Serialization explains the portable format used by default and the rules that different language runtimes must share.
3. Native Serialization explains when a same-runtime native format is appropriate.

Browse by runtime

Choose a runtime to find its installation route, lifecycle, exact APIs, configuration, type registration, schema behavior, extensions, platforms, and troubleshooting:

Runtime	Modes	Documentation
Java	xlang and native	Java runtime
Python	xlang and native	Python runtime
C++	xlang and native	C++ runtime
Go	xlang and native	Go runtime
Rust	xlang and native	Rust runtime
JavaScript/TypeScript	xlang	JavaScript/TypeScript runtime
C#	xlang	C# runtime
Swift	xlang	Swift runtime
Dart	xlang	Dart runtime
Scala	xlang and JVM native	Scala runtime
Kotlin	xlang and JVM native	Kotlin runtime

Specifications

• Xlang serialization format
• Java native object graph format
• Xlang type mapping