With Saberi and Raghavendran we constructed, in the BV formalism, the minimal, holomorphic, twist of 11-dimensional supergravity. Amazingly, on flat space, the theory shares a close relationship to an exceptional simple super Lie algebra called $E(5,10)$. Motivated by holographic duality, I’ll turn attention to symmetries of the theories on M2 and M5 branes. In the twisted setting, we find that the superconformal algebra enhances to other infinite-dimensional exceptional super Lie algebras. I will discuss further extensions of these exceptional algebras to factorization algebras and applications to pinning down correlation functions in M-theory.