---
title: Javascript-SDK - 4.0.0-rc.1
slug: feature-experimentation/release-notes/javascript-sdk-4-0-0-rc-1
docTags: 
createdAt: 2026-07-20T15:44:52.696Z
---

\## \[4.0.0-rc.1] - April 17, 2020

\### New Features
\- ES module entry point for the browser - \`"module"\` property of \`package.json\` points to \`dist/optimizely.browser.es.min.js\` (\[#445]\([https://github.com/optimizely/javascript-sdk/pull/445](https://github.com/optimizely/javascript-sdk/pull/445)))

\### Breaking Changes:
\- Dropped support for Node.js version \<8 (\[#456]\([https://github.com/optimizely/javascript-sdk/pull/456](https://github.com/optimizely/javascript-sdk/pull/456)))

\### Bug fixes
\- Node.js datafile manager uses gzip,deflate compression for requests (\[#456]\([https://github.com/optimizely/javascript-sdk/pull/456](https://github.com/optimizely/javascript-sdk/pull/456)))

[https://github.com/optimizely/javascript-sdk/releases/tag/v4.0.0-rc.1](https://github.com/optimizely/javascript-sdk/releases/tag/v4.0.0-rc.1)