A cross between Len Deighton-style espionage and H.P. Lovecraftian horror.

Bob Howard is a computer-hacker desk jockey, who has more than enough trouble keeping up with the endless paperwork he has to do on a daily basis. He should never be called on to do anything remotely heroic.

I haven't ever read Len Deighton books but I am quite familiar with H.P. Lovecraft's brand of horror. Stross does a brilliant job in mixing the newbie-to-espionage story, budding romance, and Lovecraft's alien beings ready to eat us if they get the chance to enter our universe.

I was rereading this but I recall that originally it put me strongly in mind of Poul Anderson's Operation Chaos which was a favorite of mine growing up, with the alternate universe stories of fighting evil told by a werewolf who was married to a witch. That story came to mind again when I was rereading this.

It was great fun even if some of Stross's technical explanations were so technical that I just skimmed them. You don't have to know all those details to enjoy the story.