Aquamacs is an Aqua-native build of the powerful Emacs text editor. By "Aqua-native," we mean more than just the fact that this version of Emacs runs as a standard OS X application. Aquamacs features extensive customization: it will feel and behave mostly like an Aqua program - while still being a real GNU Emacs with all the ergonomy and extensibility you've come to expect from this world-class editor. It's beeen adapted by David Reitter, based on GNU Emacs by Richard Stallman and many others.
At one point, Open Hub analyzed source code for this project based on code location(s) available at that time. Since then, the code locations have been removed.