---
title: JavaScript SDK 0.4.0
summary: null
url: >-
  https://www.fastly.com/documentation/reference/changes/2022/07/javascript-sdk-0.4.0
---

## Added

- Implement the DecompressionStream builtin [`#160`](https://github.com/fastly/js-compute-runtime/pull/160)
- Improve performace of Regular Expression literals via precompilation [`#146`](https://github.com/fastly/js-compute-runtime/pull/146)

## Fixed

- Calling `tee` on the client request no longer causes the application to hang [`#156`](https://github.com/fastly/js-compute-runtime/pull/156)