As much as I hate to just link to a wikipedia article: https://en.wikipedia.org/wiki/Clean_room_design https://en.wikipedia.org/wiki/Clean_room_design Basical

As much as I hate to just link to a wikipedia article: https://en.wikipedia.org/wiki/Clean_room_design https://en.wikipedia.org/wiki/Clean_room_design Basically, you need to find developers with no experience at all with the technology (e.g. never used Skype before), and then get another set of developers to reverse engineer the product, and send the spec to the "naive" developers, for lack of a better term.