Duckstation used to be FOSS, but then the developer Stenzek wanted complete control over the project and decided to disallow forks and third party distributions. You can still find old versions that use the GPL license, though personally I prefer to use Beetle PSX with CRT shaders and no enhancements inside of RetroArch.
Good website - bookmarked. I found something on there which I was under the impression was FOSS and had installed (Duckstation).
Duckstation used to be FOSS, but then the developer Stenzek wanted complete control over the project and decided to disallow forks and third party distributions. You can still find old versions that use the GPL license, though personally I prefer to use Beetle PSX with CRT shaders and no enhancements inside of RetroArch.