Evolution is the natural history where biological diversity is generated and retained. To expedite the evolution process in the lab to achieve specific functional optimization by artificial selection, targeted mutagenesis boosts are introduced into fast-proliferating prokaryotes and simple eukaryotes. If tolerated, the functional diversity a fast-evolving system generated offers unique opportunities to obtain artificially engineered bio-molecules best suited for bioengineering applications. In this perspective, we discuss the current state of art in vivo continuous evolution platforms, focusing on advances made in both phage and yeast artificial evolution. Their successful applications in biotechnology are presented, followed by a brief outlook of near-future developments in this burgeoning field.