The original idea was drafted by Agostino Russo taking inspiration from topologilinux, which provided a loopmounted installation, and instlux, that provided a simple Windows frontend.
The idea was to merge the two concepts having a Windows installer that would loopmount an image of Ubuntu. Geza Kovacs later refined the spec and provided the first prototypes to show that the concept was sound.
Oliver Mattos wrote the original user interface in nsis. Agostino then refined the loopinstallation concept, moving from a simple loopmounted pre-made image file, to an image created on the fly using a dynamically patched version of the debian installer, thus providing an experience much closer to a real installation and addressing several other issues.
The Lupin project was thus born. Incidentally the name “Lupin” comes from “loop-installation”, which is the technique that makes Wubi tick. Later on Agostino and Ecology2007 have redesigned and rewritten the Windows frontend, which is what people see today.
Hampus Wessman contributed the new downloader and the translation scripts. Bean123 and Tinybit also helped a lot to debug and fix bootloader issues. Lubi and LVPM were subsequently created by Geza Kovacs. Agostino Russo, Colin J Watson and Evan Dandrea have ported Lupin/Wubi into Ubuntu. Since Ubuntu 8.04, Wubi ships within the Live CD.