This mod makes projects require a bonus in order to be built. It piggybacks the existing production speed bonus, merely making it mandatory (a qualitative OR prerequisite by the way, so as long as you have any kind of speed bonus the project will be buildable). To test it start the mod on a custom future start and build a city. You can't build any projects! Now, WB uranium right onto the plot where your city is and check again. Now you can build the Manhattan Project.
This can essentially be used to make buildings prereqs for projects also: let the building provide a unique resource (akin to movies) and you can't build the project without the buildings (at least, without one in your empire).
Bonus Prereqs for Projects 2016-10-05
Bonus Prereqs for Projects