A heavy thump rolled through the corridor. He followed it around a bend and came out onto a wider service way cut through a forest of machinery. Fans turned behind mesh screens tall as walls. Pump housings shivered under load. Between them, old transit bays had been remade into work stations with tables welded from scavenged metal and bins of sorted parts. No one stood at them now, but the place still held the heat of recent work.

He crossed to the rail at the edge of a lower bay and looked down.

Crates moved on a narrow belt under him, each one sealed in pale composite and stamped with simple shape marks instead of words. Beside the belt, thick translucent lines carried nutrient slurry in slow beige pulses. Water ran in clear pipes overhead toward a bank of filters that shone blue-white in the dim. Every few seconds a lift column rose through a shaft in the ceiling, locked into place with a hard clack, and sent its load upward.

Food. Water. Air.

Not abstractly. Not as a theory about hidden infrastructure or automated support. He could see the transfer. Could smell the sour protein of processed feed where one line had been recently patched. Could hear compressed air vent and reset for the next rise. Above this ceiling sat gardens, pools, halls full of easy hands and empty answers. Beneath them, someone kept the whole illusion breathing.