Improvements to our LuaJIT benchmarking are currently being discussed in https://github.com/JuliaLang/julia/issues/14222. LuaJIT 2.1 is significantly faster than LuaJIT 2.0, but until now I haven't had a convenient way to get an installation of LuaJIT 2.1 on our test machine. LuaSci was easy to install and we would be amenable to switching over to LuaSci instead of vanilla gsl-shell. See https://github.com/JuliaLang/julia/issues/14222#issuecomment... for a timing comparison.