@executor-js/runtime-quickjs

@executor-js/runtime-quickjs

QuickJS sandbox runtime for @executor-js/execution. Runs untrusted TypeScript/JavaScript in a WASM-backed interpreter with configurable timeout, memory limit, and stack size — safe enough to execute LLM-generated code that calls your registered tools.

Install

bun add @executor-js/execution @executor-js/runtime-quickjs
# or
npm install @executor-js/execution @executor-js/runtime-quickjs

Usage

Pass a makeQuickJsExecutor() as the codeExecutor when building the execution engine:

import { createExecutor } from "@executor-js/sdk";
import { createExecutionEngine } from "@executor-js/execution";
import { makeQuickJsExecutor } from "@executor-js/runtime-quickjs";

const executor = await createExecutor({ onElicitation: "accept-all" });

const engine = createExecutionEngine({
  executor,
  codeExecutor: makeQuickJsExecutor({
    timeoutMs: 2_000,
    memoryLimitBytes: 32 * 1024 * 1024,
    maxStackSizeBytes: 1 * 1024 * 1024,
  }),
});

Options

Option	Default	Description
timeoutMs	300_000	Max wall-clock time per execution
memoryLimitBytes	64 * 1MB	Max memory the VM can allocate
maxStackSizeBytes	1 * 1MB	Max call-stack depth

Swapping the QuickJS build

import { setQuickJSModule } from "@executor-js/runtime-quickjs";
import { newQuickJSWASMModule } from "quickjs-emscripten";

setQuickJSModule(await newQuickJSWASMModule());

Use this when you want a different WASM variant (e.g. debug builds, QuickJS-NG) than the default bundled one. newQuickJSWASMModule() defaults to the release-sync variant; pass a different @jitl/quickjs-* variant to swap it.

Status

Pre-1.0. APIs may still change between beta releases. Part of the executor monorepo.

License

MIT