Given the ever-growing human population, the livestock sector is in urgent need of more sustainable feed sources and a reduction of the environmental impact. There is a rapidly growing interest in the use of insects in livestock farming, both as an alternative source of protein in animal feed and to reduce farm waste through biodegradation of manure. This project aims to develop an efficient and sustainable production method to locally rear the common housefly on-farm manure and supply the larvae as feed for production animals. Specifically, we will determine the suitability of poultry and cattle manure as feeding substrate for the housefly by investigating (1) the nutritional value of the manure and its effect on housefly larvae nutritional composition (essential nutrients and energy), (2) the optimal mass-rearing conditions for the houseflies in terms of manure type, rearing temperature, and population sex ratio. The project takes an integrated, multidisciplinary approach with a strong public-private partnership between three leading academic groups and the industrial partner Amusca who has long-term expertise with the production of houseflies and close contacts with agricultural customers. The ultimate goal is to develop a fully-closed production system that can be applied locally, mitigating the need for transport of their end product. This should lead to a significant reduction in the use of raw materials and production of waste, which will, in turn, reduce the environmental impact of the livestock industry and improve human food safety as part of a circular economy.