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I'm trying to recall a story I read several years ago. It was an urban fantasy with Greek gods involved in the plot. Our protagonist was a magical hacker of some sort, and he had a familiar, a goblin who could turn into a computer with access to magical networks. Some of the more powerful characters had "troll mainframes." The primary antagonist was Eris, and she had computers of her own: Apples. (Yes, the author really went there.)
Does this ring any bells for anyone?