APE (Another Programmer's Editor) is a terminal-based, menu-driven integrated development environment (IDE) for Unix-compatible systems.
Early development predates currently maintained BSD systems and Linux, having occurred on a 20MHz 80286 PC running Coherent, a low-cost commercial Unix-like system from the Mark Williams Company. Development shifted primarily to FreeBSD by the mid-1990s, as affordable 32-bit hardware became available, and open source operating systems came of age.
The goal of APE was to combine the efficient workflow of DOS-based IDEs such as Borland C and Microsoft QuickC with the power and stability of Unix.
APE is still actively maintained today as a common programming editor for a variety of languages. No major features have been added since the 1990s, but support for many new languages has been added to the default configuration files. APE provides basic compiler/interpreter and debugger interfacing, as well as regular expression based syntax highlighting for most popular languages, as well as a few you've probably never heard of. Support for new languages can be added by the user via dialogs under the Options menu.
As a terminal-based editor, APE functions as efficiently in a PuTTY terminal as it does on a graphical console. So, while APE does not have a graphical user interface, it can be used just about anywhere, even over the slowest of network connections to headless servers (or cloud instances) with no X11 or Wayland installation.