Websites: https://gramps-project.org/
https://www.grampsweb.org/
Source Code: https://github.com/gramps-project/gramps-web
ΒΆ Description
"Gramps Web is a web app for collaborative genealogy. It is based on and interoperable with Gramps, the leading open source genealogy desktop application. Gramps Web is free & open source software and puts your privacy and your control of your research data first."