The idea of creating a Web based IDE that creates Web based applications came to me in the exactly moment I started the Oak project. Because I started Oak using the ideas of the Borland's VCL. And I know that Delphi was made with Delphi.
And it surprised me when creating the first version was easy as thinking about how it should work. When I created the prototype, the application was almost done, because only the events were missing. Then I wrote some lines of code and the application was ready (it took about 4 hours).
But this version is very simple, because it just manage one XML file. Adding, editing and removing components from the main object. And as the component itself knows how to save and load its data there was no work to do at all, except for creating new components, calling some get and set methods. The prove is that the version 0.2 (see changelog) has 611 lines of perl code, including package headers and a weird list with almost 100 lines (that will be in a configuration file) of all the components in the addComponent.pm file.
The final version of Forest will manage the entire project. The cgi script, the xml files and the .pm files. Probably integrated with an IDE (I use xemacs, maybe this will be the first one). But I still have to mature the ideas of how a web application will change things in the user's files. At the moment I think about running a virtualHost for each user of forest as the user itself, but I'm afraid that is not a good approuch.