Scalar and GVFS (Git Virtual File System) are open-source projects developed by Microsoft, aimed at enhancing the performance and scalability of large Git repositories. They are both released under the MIT License, which is a permissive open-source license that allows for free use, modification, and distribution of the software.

The MIT License is a non-copyleft license, which means it does not have any viral or reciprocal requirements like the GPL (GNU General Public License) and other copyleft licenses. This implies that software released under the MIT License can be integrated or used in conjunction with other software, regardless of the license of the other software. This flexibility makes it possible for Scalar and GVFS to be non-GPL. As a result, developers and organizations can use these projects without any restrictions, and without having to worry about the license compatibility issues that might arise when using GPL-licensed software.