Nyamvumba was last promoted in 2018. At the time, he was promoted from Lieutenant Colonel to Colonel and appointed as the head of Defence Intelligence Department.
Prior to the appointment, he had served as the Head of Strategy and Policy in the Office of the President.
In 2019, he was named the Head of Defence Research and Development. From 2021 prior to date, he has been serving as the Head of Training and Operations in RDF.