  The CUbesat Solar Polarimeter (CUSP) project is a future CubeSat mission
orbiting the Earth aimed to measure the linear polarization of solar flares in
the hard X-ray band, by means of a Compton scattering polarimeter. CUSP will
allow us to study the magnetic reconnection and particle acceleration in the
flaring magnetic structures of our star. The project is in the framework of the
Italian Space Agency Alcor Program, which aims to develop new CubeSat missions.
CUSP is approved for a Phase B study that will last for 12 months, starting in
mid-2024. We report on the current status of the CUSP mission project as the
outcome of the Phase A.
