# nodejs Currently, `wasm-pack` generated npm modules require us to you have [fetch] polyfill in your node project. If there is a module from `wasm-pack build --target nodejs` you may encounter some errors regarding global `Headers`, `Request`, `Response` and `fetch` Web APIs. ## Common errors: ```js ReqwestError(reqwest::Error { kind: Builder, source: "JsValue(ReferenceError: Headers is not defined ReqwestError(reqwest::Error { kind: Builder, source: "JsValue(ReferenceError: Request is not defined var ret = getObject(arg0) instanceof Response; ReferenceError: Response is not defined ``` ## Workaround Import or declare fetch and objects: Headers, Request, Response ```ts // CommonJS const fetch = require('node-fetch'); // ES Module import fetch from 'node-fetch'; // @ts-ignore global.fetch = fetch; // @ts-ignore global.Headers = fetch.Headers; // @ts-ignore global.Request = fetch.Request; // @ts-ignore global.Response = fetch.Response; ``` [fetch]: https://github.com/node-fetch/node-fetch