  The ALICE Collaboration is developing a novel vertexing detector to extend
the heavy-flavour physics programme of the experiment during Run 4 by improving
the pointing resolution of the tracking, particularly at low transverse
momentum. It will be a detector with three truly cylindrical layers based on
thin wafer scale MAPS, reaching less than 0.07% X/X0 per layer and with the
innermost layer located as close as 19 mm to the interaction point. This
contribution will describe the global detector integration concept, focusing
on: the sensor bending procedure, the sensor electrical interconnection, the
choice of the best carbon foam for light mechanical supporting structures, the
studies of cooling by air flow, and the global structures mechanical
characterization.
