I'm working on bot implementation for my latest game[1]. I only ever made bots for my first game[2] but it was a breeze then. Now I needed to setup waypoints, pathfinding algorithms and some funky chasing logic but frankly I'm loving it. It's amazing how fruitful javascript community is! Libraries like rbush[3] (and really just a lot of different things by mourner) and ngraph.path[4] make things so much easier.
[1] https://redka.games/shootout [2] https://redka.games/mages [3] https://github.com/mourner/rbush [4] https://github.com/anvaka/ngraph.path