The short-lived killifish Nothobranchius furzeri inhabits ephemeral ponds in southeastern Africa and is characterized by rapid growth and early sexual maturation. With respect to the molecular, cellular, and integrative traits of aging, N. furzeri shows significant similarities to mammals, including humans. Recently, reference sequences for the N. furzeri genome have been published. Also, methods for transgenesis and genomic engineering have been established. In this review we discuss why the killifish is a valuable model for aging research and what we have learned from the genome sequence. The respective insights are not limited to the biology of aging but are also relevant for developmental biology and the evolution of sex determination.