https://en.wikipedia.org/wiki/Langton%27s_ant
antwalk_display will display an 11x11 window of the ant's progress across 2000 iterations.
antwalk_display_with_graphics will display a 16x12 animation of the ant's progress. You will need the dependencies from lua-display-grid to run it.
antwalk.lua contains the implementation.
antwalk_spec.lua contains the tests.
