Table of Contents

Backend-neutral SDK

For what the generator emits at build time and when those symbols appear, see Generated output. For the attribute reference that drives generation, see Declarations.

This page covers the full backend-neutral facade path. If you only want diagnostics, dual-runtime project setup, patch targets, Steam P2P helpers, or a few explicit member bindings, see Use cases.

Instead of writing code against ScheduleOne.* in Mono and Il2CppScheduleOne.* in IL2CPP, use generated facades under S1Interop.ScheduleOne.*.

using S1Interop.ScheduleOne.Vehicles;

LandVehicle.Handle vehicle = LandVehicle.As(rawVehicle);

if (vehicle.HasValue)
{
    string? name = vehicle.VehicleName;
    float? throttle = vehicle.CurrentThrottle;
    string? started = vehicle.StartEngine();
}

Facade namespaces preserve the original runtime namespace root:

ScheduleOne.Vehicles.LandVehicle -> S1Interop.ScheduleOne.Vehicles.LandVehicle
FishNet.Runtime.*                -> S1Interop.FishNet.Runtime.*

S1Interop does not emit shortened duplicates such as S1Interop.Vehicles.*.

Authoring model and validation targets

For this path, the goal is one source surface with generated facades, not a pile of #if MONO / #if IL2CPP branches.

Keep Mono and IL2CPP build configurations as validation targets when you have both local reference surfaces.

Type-first coverage

Use S1InteropNamespace for broad runtime type registration:

[assembly: S1Interop.S1InteropNamespace("ScheduleOne", IncludeSubnamespaces = true)]

Namespace declarations are type-only by default. They keep full-SDK builds practical without generating member facades for every type.

Use S1InteropType when mod code needs a facade for one game type:

[assembly: S1Interop.S1InteropType("ScheduleOne.Vehicles.LandVehicle")]

When metadata is available, S1InteropType can generate:

  • runtime type resolution for Mono and IL2CPP;
  • As, TryAs, and Is helpers;
  • a typed backend-neutral handle;
  • compatible public field and property accessors;
  • typed handle methods and facade invokers for unambiguous public methods.

S1InteropMember remains available for cases the type facade cannot safely infer yet: private members, better aliases, ambiguous overloads, pinned Harmony targets, and migration-specific reflection bindings.

Current limits

The facade layer favors correctness over pretending every game API is a normal C# wrapper. You will still see Handle, As, TryAs, Get<T>, Get...Value<T>, TrySet..., and Invoke.

Use named facade members first. Discovered public fields, properties, and methods use concrete signatures when metadata is safe for both backends: scalar values, string, object, void, declared enum mirrors, and game-object values whose types are also declared as S1Interop facades. Read-only fields/properties get getters; named TrySet... helpers require writable metadata.

Use S1InteropMember for private members, aliases, pinned bindings, or migration-generated reflection targets. If the binding is unresolved or ambiguous, it stays on object/generic fallback helpers.

Fall back to string-based Get, TrySet, or Invoke only when a typed facade member is not safe yet. Common blockers are overload ambiguity, generic method shape, generated backing-field metadata, incompatible Mono/IL2CPP signatures, or missing conversion rules.

Treat registry and reflection helpers as escape hatches, not the normal way to write mod code.

Edit this page