Learning software engineering is often performed ‘by doing'. Shifting to the constructivism paradigm as far as possible, we have designed an education system called «Software engineering apprenticeship by immersion» entirely based on a 7-months project, performed by a 6-students team within a virtual company and tutored by an experimented software engineer. The immersion system is skill-oriented and it may be difficult to classify system's units in a topical-oriented book of knowledge. Some individual and organizational consequences are drafted.