This page lists a few of the many extensions to MCL. Many additional extensions are included in the Examples of the MCL distribution.

• AppleEvent Suites (Terje Norderhaug) - Makes MCL and its application scriptable and recordable by implementing the classes and event handlers of the standard AppleEvent suites. Provides a framework for adding customized suites to MCL applications.
• Breakpoints (Glen Foy) - adds breakpoint functionality to MCL's stepper tool.
• Closer to MOP and ContextL (Pascal Costanza) - see the darcs repositories for MCL supported editions.
• Color Coded (Glen Foy) - lisp syntax styling for the MCL editor.
• IconRef (Terje Norderhaug) - Unified support for Carbon icons, simplifying the implementation and use of icons in menus, pop-up dialog items, and elsewhere in the user interface.
• Source Compare (Glen Foy) - GUI to a UNIX "diff" command for Lisp.
• Twist Down (Richard Lynch/Terje Norderhaug) - Displays a hierarchy in a manner similar to the traditional Finder's twist-down file browser.