The Intake claims to preserve eight billion people and rebuild a civilization for them. Four engineering checks — energy, housing, the body, and the supply chain — decide whether that's science fiction or just an unbuilt program. Run each one yourself.
The preserved population draws on the order of 0.4 TW. The Sahara — the chosen site — offers about 230 TW. The margin isn't tight; it's ~550×.
A residential ring 750 km out, 5–10 km deep, houses all 8.1 billion — and the entire global skyscraper stock holds only ~2 million. The skyline is theatre; the mid-rise ring is the city.
At the Wake, a durable synthetic body with an osmium skeleton — nearly half a tonne. Extraordinary toughness, but it can't swim, needs a heavy motorcycle to ride, and can't be repaired in the field until the supply chain exists.
From garage tools, the population must climb a 31-rung tech tree back up to a femtoscale assembler — the same tech that built the machine they live in. The catch is the whole drama: you can't skip a rung.
Energy: yes, with room to spare. Housing: yes, in the unglamorous ring. The body: hard, durable, buildable. The supply chain: a long climb, but every rung is known. None of the four checks fails. The only thing the ETI supplied that we lack is the decision to begin.