He later moved to Magta Lahjar, in the wilaya of Brakna, to complete primary and secoundary studies in the town, obtaining a baccalauréat specialised in mathematics in 1992.

[2] From 2003 to 2008, he was responsible for the monitoring and evaluation of the Education and Training project and was the Director of the Office of Specialised Studies in the field of Statistics and Economics.

[2] He became Minister of Finance in 2015 under Yahya Ould Hademine, with his portfolio later extending to also cover the Ministry of Economics following a cabinet reshuffle.

[2] During its mandate, Mauritania experienced an economic shock related to the fall in commodity prices and in particular, the fall in the price of iron ore.[3] Two months before the end of his mandate, he concluded the agreement between the Mauritanian government and the Australian company BCM International, for the exploitation of mines belonging to the National Industrial and Mining Society [fr] (SNIM) in the town of F'Déirick.

[1][7] Djay was appointed prime minister by Ghazouani on 2 August 2024 following Mohamed Ould Bilal's resignation and government reshuffle in the aftermath of the 2024 Mauritanian presidential election.