Phabricator
Phabricator is a free and open source suite of web-based Collaborative [development environment|development collaboration tools].
Its suite of tools includes Differential, a Code [reviewing software|code review tool], Diffusion, a repository browser, Herald, a change monitoring tool, Maniphest, a bug [tracking system|bug tracker], and a wiki called Phriction. It integrates with Git, Mercurial, and Subversion.
Phabricator was originally developed as an internal tool at Facebook overseen by Evan Priestley. Priestley left Facebook in 2011 to continue Phabricator's development in a new company called Phacility.
Phacility announced that it was winding down operations and placing Phabricator in a bare minimum maintenance mode in 2021, with no future updates expected.
A community fork, Phorge, was created and announced its stable release to the public on September 7, 2022, and is actively updated.