My Black Technology Shelter

Meteorites rain from the sky, blotting out the sun. Scattered shelters dot a frozen wasteland. With a nanocore in hand, Lu Chen starts by teaching himself, then uses it to bring his ideas to life, developing technology and fighting to survive. Will he one day make it into space? The story begins three days before the meteorites fall. PS: Disaster novels tend to have similar beginnings, but the story itself is different.