I *suppose* what David means is that the `BoostGSoC18/ublas` repo should actually be a fork of `ublas/ublas`. However, I have to admit that I find that not very useful. `ublas/ublas` describes itself as "Development version of Boost.uBLAS". But neither it nor `boostorg/ublas` has seen any new code in over three years, so one has to wonder how much sense such a split actually has. As far as I can tell, this just creates more work to get new code (eventually) into a release.