Client Runtime

Client runtime APIs are used by <script effect> components and by the client-side remote adapters.

import {
  ClientRuntime,
  getEffectRuntimeOrThrow,
  runComponentEffect,
  runInlineEffect
} from "svelte-effect-runtime";

Signatures

interface ClientRuntimeSeed {
  pipe(): Layer.Layer<never>;
  pipe<const Ops extends readonly [RuntimeOperator, ...Array<RuntimeOperator>]>(
    ...ops: Ops
  ): FinalRuntimeLayer<Ops>;

  make(): ManagedRuntime.ManagedRuntime<never, never>;
  make<const Ops extends readonly [RuntimeOperator, ...Array<RuntimeOperator>]>(
    ...ops: Ops
  ): ManagedRuntimeFromOps<Ops>;
}

export interface EffectRuntime<R = unknown> {
  runCallback<A, E, R2>(
    effect: Effect.Effect<A, E, R2>,
    options?: { onExit?: (exit: Exit.Exit<A, E>) => void }
  ): () => void;
  runPromise<A, E, R2>(effect: Effect.Effect<A, E, R2>): Promise<A>;
  dispose(): Promise<void>;
}

export function getEffectRuntimeOrThrow<
  T extends EffectRuntime = EffectRuntime<never>
>(): T;

export function runComponentEffect<A, E, R>(
  runtime: EffectRuntime<R>,
  program: Effect.Effect<A, E, R>
): () => void;

export function runInlineEffect<A, E, R>(
  runtime: EffectRuntime<R>,
  program: Effect.Effect<A, E, R>
): Promise<A>;

Semantics

• ClientRuntime.make(...) builds a ManagedRuntime.
• If called from hooks.client.ts, the runtime is stored globally for subsequent effect components.
• If called from a component, the runtime is also placed into Svelte context and disposed on component destroy.
• Calling ClientRuntime.make(...) again replaces the active client runtime.
• getEffectRuntimeOrThrow(), runComponentEffect(), and runInlineEffect() are generated-code helpers used by the compiler output. They are exported for runtime integration, but are internal APIs and not intended for hand-written imports.
• getEffectRuntimeOrThrow() first checks Svelte context, then the global runtime. If neither is set, a default runtime with an empty layer is created automatically. ClientRuntime.make() is optional and only needed when you want to provide custom services or layers.

Default runtime

Calling ClientRuntime.make() from hooks.client.ts is optional. When no runtime has been registered, the first <script effect> component to mount creates a default runtime automatically. This is sufficient for effects that do not depend on any custom services.

If your effects use Context services, call ClientRuntime.make(...) with the appropriate layers before any component mounts:

// src/hooks.client.ts
import { ClientRuntime } from "svelte-effect-runtime";
import { MyApi } from "$lib/my-api";
import { Layer } from "effect";

export const init = () => {
  ClientRuntime.make(Layer.provide(MyApi.Live));
};