Oh, a little more Stross: the Laundry books, starting with The Atrocity Archives. The British Secret Service has a division which guards against Lovecraftian

Oh, a little more Stross: the Laundry books, starting with The Atrocity Archives. The British Secret Service has a division which guards against Lovecraftian occult horrors --- and your narrator is one of its I.T. grunts.