Constantin gained experience in public finance, notably working for the French Ministry of the Budget, and in international investments, at Bpifrance.
At the Ministry of Budget, Constantin worked on the multi-year management of the pension system reform. At Bpifrance, he was involved in setting up investment vehicles for several Gulf sovereign wealth funds in France, and in supporting the development of sovereign wealth funds on the African continent.
Constantin is a graduate of Sciences Po Paris, with a specialization in public administration.