kotlinx.serialization¶

The kotlinx.serialization pack ships the serialization runtime (1.11.0) with no compiler plugin. The core — annotations, KSerializer, SerialDescriptor, the encoding contracts — is the upstream kotlinx-serialization-core common source, consumed from the in-pack submodule. Where upstream relies on plugin-generated serializers, klio substitutes a reflective serializer: the interpreter derives a class's serial descriptor and read/write logic from its declaration at runtime, so @Serializable classes work unmodified.

Features¶

The core is always loaded with the pack. The JSON format (kotlinx-serialization-json: Json, encodeToString, decodeFromString) is opt-in:

klio run --feature kotlinx.serialization/json app.kt

Surface¶

import kotlinx.serialization.Serializable
import kotlinx.serialization.json.Json
import kotlinx.serialization.encodeToString
import kotlinx.serialization.decodeFromString

@Serializable
data class User(val id: Int, val name: String, val tags: List<String> = emptyList())

fun main() {
    val json = Json.encodeToString(User(7, "Ada", listOf("admin")))
    println(json)                       // {"id":7,"name":"Ada","tags":["admin"]}
    val back = Json.decodeFromString<User>(json)
    println(back)                       // User(id=7, name=Ada, tags=[admin])
}

Nested @Serializable classes, collections, maps, nullable fields, and default values round-trip. The ktor pack's ContentNegotiation / json() features build on this pack (its *-serialization features pull kotlinx.serialization/json in automatically); the kotlinx.datetime pack depends on it so its value types stay @Serializable.

Install¶

./zig-out/bin/klio pack build kotlin-klio/klio-kotlinx-serialization
./zig-out/bin/klio pack install target/packs/kotlinx.serialization.klio-pack

Layout¶

Upstream core: kotlin-klio/klio-kotlinx-serialization/upstream/ (submodule, curated file list in klio.toml)
klio-supplied layer (reflective serializer(), JSON format): kotlin-klio/klio-kotlinx-serialization/klioMain/
Native impl: src/kotlinx_serialization/kotlinx_serialization.zig
Manifest: kotlin-klio/klio-kotlinx-serialization/klio.toml