Hardware
Physical engineering with a machine that has never touched your bench.
Requires The Book of Works
IThe datasheet outranks memoryThe model has read a thousand datasheets; yours is rev B. Feed it the document, then make it derive.IIMeasure, don't eyeballGeometry, timing, thresholds: every constant traces to a spec, a calibration, or a measurement you just took.IIIVendors and partsBOMs, sourcing, and price claims verified like any other claim: against a real listing, a real quote, a real human.