Descent.RngKit.Serialization 0.1.0

Descent.RngKit.Serialization

Opt-in System.Text.Json serialization for Descent.RngKit — a zero-allocation, never-throw dice expression engine for high-concurrency virtual tabletops.

This package contains one type: RngKitJsonContext, the source-generated JsonSerializerContext for RngAuditPacket and the contracts it carries. It depends on Descent.RngKit.Abstractions and nothing depends on it.

dotnet add package Descent.RngKit.Serialization --version 0.1.0

Pre-1.0. Below 1.0.0 the public API is unstable by declaration — SemVer permits breaking changes in any 0.x minor release — so pin an exact version rather than a floating range.

Usage

using System.Text.Json;
using Descent.RngKit.Serialization;

string json   = JsonSerializer.Serialize(packet, RngKitJsonContext.Default.RngAuditPacket);
var    packet = JsonSerializer.Deserialize(json, RngKitJsonContext.Default.RngAuditPacket);

Source-generated rather than reflection-based, so it is Native AOT and trim safe: no IL2026/IL3050 warnings and no runtime code generation. Polymorphic IRngMetadata payloads round-trip through the [JsonPolymorphic] / [JsonDerivedType] discriminators declared on the interface in Descent.RngKit.Abstractions.

Why this is a separate package

Descent.RngKit.Abstractions describes what a roll result is. It takes no position on how you put it on a wire, so a host using MessagePack, protobuf, or any other format does not carry a JSON serializer in its contract layer.

Splitting it out took Descent.RngKit.Abstractions.dll from 261,632 to 100,864 bytes (−61.5%), both measured on the x64 Release build. That is worth having for NuGet download size, for framework-dependent deployments, and for hosts that map contract assemblies into per-plugin AssemblyLoadContext sandboxes, where each loaded assembly costs metadata.

It does not shrink a Native AOT image, and it was never going to. ILCompiler already strips an unreferenced JsonSerializerContext — it is an ordinary class, and nothing about [JsonSerializable] roots it. A non-serializing consumer measured byte-identical before and after the split: 3,880,448 bytes either way. The general point, since it is easy to get wrong: under Native AOT the unit of dead-code elimination is reachability, not assembly, so splitting a package is not a trimming strategy. The control experiment is recorded in §3.1a of the multi-angle review.

Links

• 📦 Descent.RngKit.Abstractions — the contracts
• 📦 Descent.RngKit — the engine
• 📦 Descent.RngKit.Mechanics — the standard ruleset library
• 📘 Syntax reference

MIT © DescentVTT Team