Karabiner doesn't work at all with Sierra. There's some "new" project called Karabiner Elements is supposedly half-finished, but yet people keep donating hoping they'll get something usable soon. Not holding my breath and it would be completely new and will likely lack useful features of the abandoned one.

It would be more useful to more people to temporarily fix Karabiner and work on Elements later, but no, gotta ignore paying users and stick to "the plan."