Hi,
It's quite niche, it has evolved into a library for computing various things involving Schubert calculus. The last release is pretty far behind personal development, but the basic features are usable and primarily about computing structure constants of flag varieties of various kinds (including equivariant, Molev-Sagan, for both quantum and classical Schubert calculus, with quantum including parabolic quotients). The repository is being cloned, but I do not have any idea who is doing it. I started the discussion board linked above for anyone who is using it actively. Please contact me if you have any questions.
Thanks,
Matt