[gutvol-d] How are the ebook files generated?

I've nearly finished producing my first text for PG and, in order to test the HTML, I've been viewing it in Firefox and also using kindlegen to convert it to Mobipocket format, which I'm then using a Kindle to view. I've been hunting for details of the current conversion process on the Wiki, and haven't come across any concrete information about how PG does the conversions. Could anyone please point me to the documents or software that are used?