kotlinx-serialization

What problem does it solve?

Kotlin Multiplatform projects often struggle to implement consistent, robust serialization across platforms and boundaries. This Skill provides guidance on configuring JSON with a shared Json instance, managing polymorphism with sealed hierarchies, and applying custom serializers to ensure stable wire formats in Ktor, SQLDelight, and settings values.

Core Features & Use Cases

• Centralized Json configuration for KMP with sensible defaults and safe deserialization behavior.
• Polymorphic models using sealed hierarchies and discriminators for forward-compatible APIs.
• Custom serializers and enum handling to align Kotlin types with wire formats and server expectations.
• Practical use cases across Ktor bodies, SQLDelight blobs, and cross-platform data transfer.

Quick Start

Configure a shared Json instance, annotate common and platform-specific data classes with @Serializable, and start using kotlinx-serialization in your KMP modules.