Copyright: (C) 1996-2023 Free Software Foundation, Inc.


The GNUstep GUI library is a free software package implementing the API of the OpenStep Application Kit (tm), or "AppKit", including later additions. This documentation package describes the core of the Base library; for documentation on additional classes, see the GuiAdditions documentation package.

Read the Release Notes for the current release.


GNUstep is generally compatible with the OpenStep specification and with recent developments of the Mac OS X (Cocoa) API. Where MacOS deviates from the OpenStep API, GNUstep generally attempts to support both versions. In some cases the newer MacOS APIs are incompatible with OpenStep, and GNUstep usually supports the richer version. See the OpenStep Compliance section for more information on OpenStep Compliance.

Information and Setup

Nicola Pero has begun work on writing an introduction to the basic concepts and use of the GNUstep GUI library.

Useful documentation for setting up GNUstep:

API Documentation

Class Protocol