nx_bootstrap.nx

nx_bootstrap.nx -- LIB: the DOOMSDAY self-sufficiency + ROI model. Scales the digital-twin/supply-chain capability from a single product up to the WHOLE fabrication bootstrap: the chain of machines/processes from the tiniest input (feedstock) up to making our OWN CPUs/GPUs. Each stage carries real numbers: capital cost (cents), build time (days), value produced (cents/day), and self_made (1 = we can build it from lower stages in-house, 0 = a must-buy "vitamin"). Computes SELF-SUFFICIENCY (permil makeable in-house), per-machine ROI/PAYBACK days, and the BOTTLENECKS (what stays bought -- chips, steppers per Gershenfeld). The leverage: closing the chip bottleneck (garage litho / additive CPU printing) is the biggest self-sufficiency jump. Inputs are RESEARCH-GROUNDED ESTIMATES (RepRap/OSE/Zeloof/CMU Hacker Fab); the rollup MATH is exact. never-brick #26: pure arithmetic, deterministic. license_tier: ORIGINAL