  MOSAIC is the planned multi-object spectrograph for the 39m Extremely Large
Telescope (ELT). Conceived as a multi-purpose instrument, it offers both high
multiplex and multi-IFU capabilities at a range of intermediate to high
spectral resolving powers in the visible and the near-infrared. MOSAIC will
enable unique spectroscopic surveys of the faintest sources, from the oldest
stars in the Galaxy and beyond to the first populations of galaxies that
completed the reionisation of the Universe--while simultaneously opening up a
wide discovery space. In this contribution we present the status of the
instrument ahead of Phase B, showcasing the key science cases as well as
introducing the updated set of top level requirements and the adopted
architecture. The high readiness level will allow MOSAIC to soon enter the
construction phase, with the goal to provide the ELT community with a
world-class MOS capability as soon as possible after the telescope first light.
