Click here to see how OpenACS shows you how its pages are composed Web toolkits sometimes to evolve to the point where it becomes hard to figure out what file is responsible for a particular part of the page, and consequently difficult to debug or modify those pages when debugging or modification is necessary. It’s a byproduct of getting the ability to nest a page in a standard frame, or being able to include resuable templates from a template library. OpenACS mitigates the difficulty by running in a “developer mode” that lets you see where the different parts of the page come from.