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@@ -964,6 +964,7 @@ Table of Contents
    * [cacher.io](https://www.cacher.io) — Code snippet organizer with labels and support for 100+ programming languages.
    * [codesnip.com.br](https://codesnip.com.br) — Simple code snippets manager with categories, search and tags. free and unlimited.
    * [cocalc.com](https://cocalc.com/) — (formerly SageMathCloud at cloud.sagemath.com) — Collaborative calculation in the cloud. Browser access to full Ubuntu with built-in collaboration and lots of free software for mathematics, science, data science, preinstalled: Python, LaTeX, Jupyter Notebooks, SageMath, scikitlearn, etc.
+   * [ide.cs50.io](https://ide.cs50.io/) - A free IDE powered by AWS Cloud9 by Harvard University.
    * [codepen.io](https://codepen.io/) — CodePen is a playground for the front end side of the web.
    * [codesandbox.io](https://codesandbox.io/) — Online Playground for React, Vue, Angular, Preact and more.
    * [Eclipse Che](https://www.eclipse.org/che/) - Web based and Kubernetes-Native IDE for Developer Teams with multi-language support. Open Source and community driven. An hosted version is available at [che.openshift.io](https://che.openshift.io/)