A flux pump is a device that injects or extracts magnetic flux from a closed superconducting loop without a continuous pair of current leads, by repeatedly driving a small region of the loop normal and then letting it recover so that flux ratchets across it. It lets a persistent winding be charged, discharged, or actively trimmed while remaining a closed, low-dissipation circuit. In the splinky, an integrated flux pump drives each ring’s transverse trim-saddle windings, so lateral steering needs no continuous leads and dissipates only switching losses.