---
title: "License"
---

SLRE is released under commercial and [GNU GPL
v.2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html) open source
licenses.

Commercial Projects: Once your project becomes commercialised GPLv2 licensing
dictates that you need to either open your source fully or purchase a
commercial license. Cesanta offer full, royalty-free commercial licenses
without any GPL restrictions. If your needs require a custom license, we’d be
happy to work on a solution with you. [Contact us for
pricing](https://www.cesanta.com/contact).

Prototyping: While your project is still in prototyping stage and not for sale,
you can use SLRE’s open source code without license restrictions. 

[Super Light DNS Resolver](https://github.com/cesanta/sldr), [Mongoose web
server](https://github.com/cesanta/mongoose) are other projects by Cesanta
Software, developed with the same philosophy of functionality and simplicity.