Example of Node, Typescript, and Comlink

index.ts

import { getRemoteAPI } from "./my_worker";

async function init() {
  console.time("launch");
  const api = getRemoteAPI();
  console.timeLog("launch");
  console.time("first result");
  console.timeLog("first result", await api.doMath());
  console.time("second result");
  console.timeLog("second result", await api.doMath());
  await api.doMath();
}
init();

my_worker.ts

import { parentPort, Worker, isMainThread } from "worker_threads";
import * as Comlink from "comlink";
import * as nodeEndpoint from "comlink/dist/umd/node-adapter";

const api = {
  doMath() {
    return 4;
  }
};

export type API = typeof api;

export function getRemoteAPI(): Comlink.Remote<API> {
  // Have to hack for typescript. `worker.js` is a wrapper that loads whatever
  // we specify in `workerData.path`.
  const worker = new Worker("./worker.js", {
    workerData: {
      path: "./my_worker.ts"
    }
  });

  return Comlink.wrap(nodeEndpoint.default(worker));
}

// Because we are using this file on the main thread (to have the helper available)
if (!isMainThread && parentPort) {
  //Comlink.expose(api, nodeEndpoint.default(parentPort));
}

worker.js

const path = require("path");
const { workerData } = require("worker_threads");

require("ts-node").register();
require(path.resolve(__dirname, workerData.path));

Output:

$ ts-node index.ts
launch: 6.881ms
first result: 877.905ms 4
second result: 0.201ms 4