MacPorts was originally started as DarwinPorts as part of the OpenDarwin initiative at Apple [1]. Apple continued to sponsor MacPorts by providing hosting of website, repository, and build servers at Mac OS forge [2] until it closed back in 2016. The project then moved to GitHub and their own servers.
[1] https://trac.macports.org/wiki/MacPortsHistory
[2] https://www.macosforge.org/