Winner of the Hugo and John W. Campbell awards.
What I found most interesting about this novel was the portrait of a non-humanoid species that had evolved on a planet with a variable sun. Once each generation, the star dims and the planet goes through a long "winter" in which even the atmosphere freezes, so life must hibernate in hidden places. When the star brightens and the planet warms up again, life makes a frenzied effort to do as much as it can before the next freeze. The people of the planet ("spiders") are fairly new to industrialization. The generation we are introduced to is the first to have a genius who sees a way to use technology so society and the spiders can continue functioning during the "winters".
But this is also happening at a time when two antagonistic human expeditions have come to the star system to investigate radio signals from the planet that had been detected. A space battle between the two expeditions has left both disabled in space, but the more predatory of the two groups has taken a dominant position over all the survivors. During the years it takes to rebuild their ships in space, the spiders on the planet have a chance to develop further before having to deal with the human aggressors. But partly, the humans have been waiting for the planet to develop technology the humans need.
Also during this period, a member of the other human group prepares to act against the predators. A major part of his work involves nanomachines, programming and such technology that could appeal to fans of cyberpunk. The effort is difficult because the predators are very skillful rulers, manipulators, spies and tricksters. They also have a form of mind control they use on some prisoners. It is a long, twisty and elaborate conspiracy.
The spiders are not a united, peace-loving species either. The competing spider nations find the periods when most spiders have gone into hibernation at the beginning of "winter" and before most spiders have come out of hibernation to be strategic times to maximize their relative positions. Therefore technology to extend when soldiers can function has played a role in the developing new science. And when one nation plans to use technology to allow their society to function through the whole "winter", other nations view this as a serious threat to their future. The modernization also provokes religious fundamentalists into actions that complicate matters.
The part of the story about the struggle among the humans is well done, but would not have made a book I would have picked to read if the people on the planet were just a third group of humans. However, with the fine presentation of a different kind of planet, a non-human species and their societies, this becomes a very desirable book.