# Fix 'util.pump is not a function' in Node.js

> Learn how to fix the util.pump is not a function error in Node.js, caused by old code; replace the removed util.pump with pipeline from the stream module.

Author: [Flavio Copes](https://flaviocopes.com/about/) | Published: 2020-08-17 | Topics: [Node.js](https://flaviocopes.com/tags/node/) | Canonical: https://flaviocopes.com/node-solve-pump-not-function/

If you experience the error "util.pump is not a function" while running a [Node.js](https://flaviocopes.com/nodejs/) app or a Node.js snippet, it's because the app code is too old for the current Node.js runtime.

The `pump()` method that Node.js provided wrote a readable [stream](https://flaviocopes.com/nodejs-streams/) to a writable stream using this syntax:

```js
util.pump(readableStream, writableStream)
```

This method is now gone, deprecated for a long time and removed when Node.js 6.0 was released in April 2016.

Luckily, it's easy to fix this problem.

Replace the above syntax with:

```js
const { pipeline } = require('stream')

//...

pipeline(readableStream, writableStream, () => {})
```

The third argument is a callback function that will be called when the pipeline is done.

[Read more on `pipeline` here](https://nodejs.org/api/stream.html#stream_stream_pipeline_source_transforms_destination_callback).