Scripting techniques are used in various contexts. The field of application ranges from layout description languages (PostScript), user interface description languages (XUL) and classical scripting languages (JavaScript) to action nodes in scene graphs (VRMLScript) and web-based desktop applications (AJAX).All these applications have an increase of scripted components in common -- especially in computer graphics. As the interpretation of a geometric script is computationally more intensive than the handling of static geometry, optimization techniques, such as just-in-time compilation, are of great interest. Unfortunately, scripting languages tend to support features such as higher order functions or self-modification, etc. These language characteristic are difficult to compile into machine/byte-code. Therefore, we present a hybrid approach: an interpreter with an integrated compiler. In this way we speed up the script evaluation without having to remove any language features e.g. the possibility of self-modifications. We demonstrate its usage at XGML -- a dialect of the generative modeling language GML, which is characterized by its dynamic behavior.