Modifies the sleep cycle using genes from species that achieve rest through unihemispheric sleep — dolphins and migratory birds that sleep with half their brain at a time. The modification doesn't eliminate sleep but compresses it: the user achieves full cognitive and physical recovery in 2–3 hours instead of 7–8, and the sleep is lighter, with easier arousal. Some installations allow a 'dolphin mode' where one brain hemisphere sleeps while the other remains conscious — the user appears awake and functional but is resting half their brain. Productivity gains are enormous: 4–6 extra hours of functional time per day. The modification is standard among Tier 5 executives, ubiquitous in demanding corporate roles, and increasingly common among Tier 3 professionals who can't afford to sleep while their modified colleagues work. It is, in effect, mandatory in any competitive field where it's available.