This paper shows how the colonial past has to be taken into account to explain racial discrimination processes on the labor market in Western Europe. Focusing on the French case, and more particularly on the Algerian migrants in France, the paper will reassess the ‘postcolonial bonus hypothesis’ concerning migrant professional careers in the French industry. The study presented is based on extensive research in the Renault factory, one of the biggest French factories and one of the main employers of Algerian workers in the "Thirty Glorious Years". It presents an original study intersecting archives, interviews and the processing of statistical data on the careers of 1000 Algerian workers in the automobile industry from 1950s to 1980s – fieldwork exposed in a book to be published in 2014 (Algériens au travail : une histoire coloniale, Presses universitaires de Rennes). The paper demonstrates how, even in a factory renowned as a "social laboratory", colonial racism lastingly marks these workers’ careers, well beyond the Independence of Algeria in 1962. More widely, by exploring various (post) colonial logics of domination in situ, this paper points out how colonial racism takes part into the genealogy of social class and race relations in today’s French society.