Taken together, we successfully engineered Hypocrea in a way that this fungus now produces NeuNAc from the biopolymer chitin by employing its natural saprophytic activity in combination with the introduction of a bacterial enzyme cascade. Because human society will face severe bottlenecks in the supply of energy and in obtaining certain raw materials in the upcoming years, we hope that this study will highlight the potential advantages of biopolymers, such as chitin, and stimulate their efficient usage. Furthermore, we anticipate that such strategies will support efforts to create sustainable production processes.