CoreWeave is bigger – $2.08 B quarterly revenue (+112%), a ~$99 B backlog – and more fragile: $21‑25 B of debt at 9‑15% effective rates, GPU‑collateralized SPVs tied to single contracts, and a $4.2 B 2026 maturity wall. My six‑test scorecard flags Nebius’s supposed diversification as a falsifier, since >90% of its backlog appears tied to Microsoft and Meta (inferred). Both firms sit on the bottom rung of the durability ladder, renting the same chips and power and owning only leverage and spread.