  I introduce an energy constrained approximate twirling operation that can be
used to diagonalize effective logical channels in GKP quantum error correction,
project states into the GKP code space and construct a dynamical decoupling
sequence with fast displacements pulses to distill the GKP stabilizer
Hamiltonians from a suitable substrate-Hamiltonian. The latter is given by an
LC-oscillator comprising a superinductance in parallel to a Josephson Junction.
This platform in principle allows for protected GKP quantum computing without
explicit stabilizer measurements or state-reset by dynamically generating a
`passively' stabilized GKP qubit.
