The smell was a warning, hot, organic and yeasty like fresh-baked bread, with an underlying tang of metal, blowing across my chemosensors as I crashed into the apartment; the characteristic effusions of an active nanosystem.  It was a useful warning, since this amateur nanohacker had ignored the procotols and the caution-warning channel was silent but for the emergency-in-progress tags I and building management had posted manually.

But it was also a redundant warning.  The bloom was already macroscopic, gaping gaps showing in the ceiling and wall paneling where nanites had harvested them for materials.  I punched through the hole-riddled remnant of the wall that separated the atrium from the apartment’s main room, spraying around me with abandon the chemical nanobinder semi-affectionately known as ‘phlegm’, and brought myself up short.  The center of the floor had collapsed into the utility space, and the remnants of a chair and a table that had probably once contained lab equipment had now mostly deliquesced into the domed pseudopuddle below.  All that remained of the chair’s occupant were the hard-to-digest fragments of a carbon-reinforced skeleton, still gleaming with the rainbow colors of machine-phase nano.  This was clearly the center of the outbreak.

A vector stack was still pinging from one side of the puddle, though, so I selected a justheart from my panniers and lofted it as close as I could to the stack’s location.  It shattered on impact, the liquid nitrogen pouring out already boiling and freezing the puddle medium.  Good.  Citizen Idiot should be back in time to to face the foot-high stack of lawsuits this venture had already bought him.

Spraying more phlegm, targeted now to coat and seal off the pseudopuddle, I moved in to sample and contain…