I created a javascript library using webpack

I added the file into my react application:

import {Helmet} from "react-helmet";
ReactDOM.render(
  <React.StrictMode>
    <Helmet>
       <script src="/static/lib.js"/>
    </Helmet>
    <App />
  </React.StrictMode>,
 document.getElementById('root')
 );

when I was checking the site sources - I found out that lib.js exists in there. I have a component that needs to create an object that exists inside the lib.js file

#myComponent.js
class MyComponent extents Component {
    constructor(){
      this.obj = new MyObject() // here is the problem
    }
}
    render() {
       return <div className="main-background">
         some stuff
        </div>;
    }
}

I suspect that the problem has something to do with DomReady - the library probably doesn't get loaded and the module is not defined