@voyd-lang/js-host

Thin JS host implementation for the Voyd host protocol.

import { createVoydHost } from "@voyd-lang/js-host";

const host = await createVoydHost({ wasm });
host.registerHandler("com.acme.log", 0, "0x91f2abcd", (msg) => console.log(msg));
host.initEffects();

const result = await host.run("main");

createVoydHost installs default std capability adapters by default (voyd.std.fs, voyd.std.time, voyd.std.env, voyd.std.random, voyd.std.log, voyd.std.fetch, voyd.std.input). Disable with defaultAdapters: false if you want full manual handler control.

Advanced control (fairness + cancellation):

const host = await createVoydHost({
  wasm,
  scheduler: { maxInternalStepsPerTick: 1024 },
  defaultAdapters: false,
});

const run = host.runManaged("main");
// run.cancel("user-request");
const outcome = await run.outcome;

Runtime wasm traps now include structured Voyd context on error.voyd:

try {
  await host.run("main");
} catch (error) {
  if (error instanceof Error && "voyd" in error) {
    const trap = (error as Error & { voyd: unknown }).voyd;
    console.error(trap);
  }
}

error.voyd includes the nearest mapped Voyd function/span (when available), and for effect resume traps it also includes effect op metadata and transition context (point/direction).

Deterministic runtime harness for scheduler/adapter conformance tests:

import { createDeterministicRuntime } from "@voyd-lang/js-host";

const runtime = createDeterministicRuntime({
  startMonotonicMs: 0,
  startSystemMs: 1_700_000_000_000,
});

const host = await createVoydHost({
  wasm,
  scheduler: { scheduleTask: runtime.scheduleTask },
  defaultAdapters: {
    runtime: "node",
    runtimeHooks: {
      monotonicNowMillis: runtime.monotonicNowMillis,
      systemNowMillis: runtime.systemNowMillis,
      sleepMillis: runtime.sleepMillis,
    },
  },
});