  We propose a strategy for engineering multi-qubit quantum gates. As a first
step, it employs an eigengate to map states in the computational basis to
eigenstates of a suitable many-body Hamiltonian. The second step employs
resonant driving to enforce a transition between a single pair of eigenstates,
leaving all others unchanged. The procedure is completed by mapping back to the
computational basis. We demonstrate the strategy for the case of a linear array
with an even number N of qubits, with specific XX+YY couplings between nearest
neighbors. For this so-called Krawtchouk chain, a 2-body driving term leads to
the iSWAP$_N$ gate, which we numerically test for N = 4 and 6.
