In the long arc of energy transition, promise and proof are separated by years of permitting, construction, and capital patience. Deep Fission, a developer of small modular reactors built on mature pressurized water technology, has assembled an 18.5 gigawatt customer pipeline that speaks to genuine market interest — yet an analyst cautions that interest is not the same as income. The distance between a letter of intent and a functioning reactor is measured not in gigawatts, but in time, execution, and the quiet discipline of waiting for milestones that matter.