The Skyline project is developed in open source, under Apache 2.0 License, though released under a modified Apache 2.0 License, due to the inclusion of third party libraries with licensing restrictions.

The source code for Skyline is made available through the ProteoWizard GitHub Repository. The main Skyline project can be found under:

pwiz_tools/Skyline

If you are interested in working with the Skyline source code, follow the "How to build Skyline" instructions.