# Parse the IFC, again

We have now a working script (without Three). Let's finish the `Web Worker`. Also, don't forget to generate the new build file. 

```javascript
importScripts('../libs/chevrotain.min.js');
importScripts('../../build/IFC.workerr.js');
onmessage = (e) => {
    const ifcData = e.data; 
    const loaded = IFCjs.loadIfcFileItems(ifcData);
    const structured = IFCjs.constructProject(loaded);
    postMessage(structured);
};
```

Please note that our build is dependent on Chevrotain, but not Three. We need to import Chevrotain first (!).

Of course, our `Web Worker` will not work. We dissuced this problem in [Single Web Worker Example](https://bimwhale.gitbook.io/ifc-js/web-worker-example/single-web-worker-example). We need to remove the `mainObject`.