Nanny was part of la Société de concerts des Instruments anciens. He gained some international exposure as a composer during his lifetime, although he never enjoyed the respect he received in France worldwide. Among his most famous works are his Concerto in E minor and his Consignment Complet (a collection of pedagogical works including the 2-part Méthode complète pour la contrebasse à quatre et cinq cordes, the Vingt études de virtuosité, and his Dix étude-caprices). Additionally, the Concerto in A major that was attributed to classical Italian virtuosoDomenico Dragonetti was, in fact, penned by Nanny.
Although his two concertos (his own and the musical hoax under Dragonetti's name) are important repertory items, Nanny's most lasting contribution was in the field of pedagogy. His études and caprices are still played by double bass students.