I really need to make an updated blog post about it, but this project evolved into a reasonably-well-debugged Cray J90 core that fits quite comfortably in a Xilinx Artix-7 35T board (I made a somewhat bulky Cray J90 Smartwatch that tells time by running a real-time n-body simulation of Jupiter and 63 of its moons . . . inferring the current time is left as an exercise for the viewer).