# [s3.js](https://git.rootprojects.org/root/s3.js) | a [Root](https://rootprojects.org) project > Minimalist S3 client A lightweight alternative to the s3 SDK that uses @root/request and aws4. * set() * get() * head() * delete() ```js s3.set({ accessKeyId, secretAccessKey, region, bucket, prefix, key, body, size }) ``` If the body is a stream then `size` must be set to `fs.statSync(filePath).size`, or the request will fail: ``` 501 NotImplementedA header you provided implies functionality that is not implemented ```