  A Large Ion Collider Experiment (ALICE) has been conceived and constructed as
a heavy-ion experiment at the LHC. During LHC Runs 1 and 2, it has produced a
wide range of physics results using all collision systems available at the LHC.
In order to best exploit new physics opportunities opening up with the upgraded
LHC and new detector technologies, the experiment has undergone a major upgrade
during the LHC Long Shutdown 2 (2019-2022). This comprises the move to
continuous readout, the complete overhaul of core detectors, as well as a new
online event processing farm with a redesigned online-offline software
framework. These improvements will allow to record Pb-Pb collisions at rates up
to 50 kHz, while ensuring sensitivity for signals without a triggerable
signature.
