First-class constraints and the BV formalism
  Employing the Batalin-Vilkovisky (BV) formalism, we present a systematic and simple prescription to derive (first-class) constraints including the Hamiltonian constraint (a.k.a. flow equation), which plays pivotal role in holographic computation of Weyl anomalies. In this method, you do not have to compute canonical momenta nor Hamiltonians. Thus it may equip us with a `Lagrangian treatment' of constrained systems. We also point out an interesting analogy between antifields and first-class constraints. 
Ken Kikuchi
hep-th