Do you use Emacs or XEmacs (or have used it in the distant past!)? That is because it lets you to customize using Emacs Lisp? Then, you probably would be interested in this: Chuk has written A Simple Scripting Enviroment for NetBeans. This is a NetBeans module for scripting NetBeans! Currently, it supports JavaScript only -- although it uses javax.script API and hence it could be made to use any JSR-223 script engine - including Scheme!