Valkyrie's War — Dietmar Arthur Wehr

Valkyrie's War is a short, military SF novel, set in the Synchronicity War/Retro War universe. It's an action-packed story where the Artificial Intelligence, Valkyrie, and her AI soul mate, Casanova, discover that all of humanity is in deadly danger, and the two of them are humankind's only hope. But this time, they're not facing a biological threat. This time the enemy is another AI that is far more capable than they are. If you enjoyed The Synchronicity War's clash of space fleets and time travel, then you'll enjoy this stand-alone sequel to The Retro War.