---
title: Android Support
sidebar_position: 6
id: android_support
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.
---

Apache Fory Kotlin supports Kotlin/JVM and Android. Android support is built on
the existing Fory Java runtime plus Kotlin runtime serializers from
`fory-kotlin`. Kotlin schema serializers are generated by `fory-kotlin-ksp` at
build time.

Use this page for Android setup and release-build constraints. Use
[Static Generated Serializers](static-generated-serializers.md) for the Kotlin
KSP serializer model itself. If your Android project also contains Java
`@ForyStruct` classes, use the Java annotation processor documented in
[Java Static Generated Serializers](../java/static-generated-serializers.md).

## Dependencies

Add `fory-kotlin` to the Android module that uses Fory. Add
`fory-kotlin-ksp` to the module that compiles Kotlin `@ForyStruct` model
classes.

```kotlin
plugins {
  id("com.android.application")
  id("org.jetbrains.kotlin.android")
  id("com.google.devtools.ksp")
}

dependencies {
  implementation("org.apache.fory:fory-kotlin:<fory-version>")
  ksp("org.apache.fory:fory-kotlin-ksp:<fory-version>")
}
```

For Android library modules, apply KSP in the library module that owns the
annotated Kotlin classes. The generated serializers and generated consumer R8
rules must be packaged with that library artifact.

## Runtime Setup

Create the runtime with `ForyKotlin.builder().withXlang(true)`, then register application classes
through the Kotlin `register<T>` extension or the normal Fory Java registration
APIs.

```kotlin
import org.apache.fory.kotlin.ForyKotlin
import org.apache.fory.kotlin.register

val fory = ForyKotlin.builder()
    .withXlang(true)
    .requireClassRegistration(true)
    .build()

fory.register<User>("example", "User")
```

Do not reference generated serializer classes from application code. The runtime
resolves generated serializers from the registered target class.

## Xlang Schema Mode

Android Kotlin structs that participate in Fory cross-language schema
serialization should use KSP generated serializers. Generated serializers avoid
using runtime reflection as the source of Kotlin schema metadata and call the
same Fory Java runtime infrastructure used by other generated serializers.

Kotlin KSP generated serializers are xlang/schema serializers only. They do not
replace Java native object serializers and do not preserve concrete JVM
collection implementation identity. For example, a Kotlin `List<String>` field
is schema `list<string>`; deserialization only guarantees a value assignable to
the declared field type.

## Minified Release Builds

Validate Fory Android behavior with a minified release build. Debug builds do
not prove that generated serializers, generated constructor entry points, or
Kotlin metadata survive R8.

KSP emits generated consumer R8/ProGuard rules under `META-INF/proguard/` for
the generated serializer constructors and Kotlin metadata required by Fory.
Android apps should not need broad user-written keep rules for generated Kotlin
serializers. If a custom packaging setup drops generated `META-INF/proguard/`
resources, fix that packaging path instead of adding broad keep rules for every
generated serializer.

The Apache Fory repository validates this path with
`integration_tests/android_tests`, including release-minified instrumented
tests.

## Java Models In Android Apps

Kotlin KSP only processes Kotlin source. If your Android app contains Java
classes annotated with `@ForyStruct`, configure the Java
`fory-annotation-processor` for those Java sources.

Static generated Java serializers are also important on Android when Java model
classes use Fory type-use annotations on nested types, such as
`List<@UInt8Type Integer>`. See
[Java Static Generated Serializers](../java/static-generated-serializers.md)
for that path.

## Unsupported Targets

`fory-kotlin` and `fory-kotlin-ksp` target Kotlin/JVM and Android only.
Kotlin/Native and Kotlin/JS are not supported.