He earned his National diploma (Brevet d'Etudes du Premier Cycle), a preparatory course for the Académie des Arts et Métiers in Marseille.
At age 17, he sent his résumé to Citroën, one of the major automobile manufacturers in France, where he was hired to maintain equipment.
[5] In 1936 he became a technical draftsman, and in January 1942, CEO Pierre-Jules Boulanger assigned him to the development department to solve problems with braking and suspension systems (including for the Citroën 2CV).
[7] This questioning led to the eventual development of a hydro-pneumatic suspension system, which combined an easily compressible gas in an enclosed chamber with the non-compressible, force-multiplication properties of hydraulic machinery.
The 1955 Citroën DS, developed around Magès' engineering innovations, placed third in the 1999 Car of the Century competition, behind the Ford Model T and the BMC/BL Mini.