Robin Sloan's 2012 novel, Mr Penumbra's 24-Hour Bookstore, was as strong a debut as you could ask for, an instant geek classic of bibliophilia, magic and technology; now, with today's release of Sourdough, Sloan returns to the alienated, quirkily funny and brilliant lives of technology workers, in a tale of food, the flesh, novelty-seeking, ancient tradition, and immortal colony-organisms.

Lois Clary is a transplanted Michigander who was wooed away from her big-iron control-systems job in Detroit to a sparkling, cult-like robotics startup in San Francisco, where she is teaching a robot arm to replace all human labor, one task at a time.

San Francisco dashed Lois's dreams in familiar ways: she can't quite get the hang of the cult-like work/life imbalance her co-workers find so effortless, not even after she switches from solid food to Slurry, an engineered glop that frees her from the drudgery of enjoying eating

But things change for Lois the day she places an order from a weird-seeming takeout joint that put a menu under her door and discovers the amazing world of the cuisine and culture of the Mazg, a strange hidden-in-plain sight ethnic minority whose Number Two Spicy soup and its accompanying sourdough makes her stomach stop hurting for the first times since she got to San Francisco.

As quickly as her life is transformed by Mazg cuisine, it is snatched away from her — the brothers who've been cooking for her move back to the UK, scared away by Trumpian rhetoric about deporting immigrants and a desire for a different life. They leave behind a sourdough starter — the fabled Mazg sourdough starter — and a CD of Mazg music, and teach her to bake a loaf before they go.

Thus begins Lois's adventures in baking and her ruminations on the physical and the microbial and the robotic and how they all cross over. The more she bakes, the more important it becomes to her, until she finds herself invited to join the crew at a mysterious invitation-only food market in an underground former military base on a windswept island in the San Francisco Bay, where she discovers that baking has taught her everything she needs to program a surplus robot-arm to break through some of the hard problems of robotic sous-chefing.

The ensuing tale is one that plunges through so much terrain: microbial nations, assimilation and tradition, embodied consciousness and the crisis of the tech industry, all without losing the light, sweet, ironic Sloanian voice familiar from Mr Penumbra's, a plot that makes the book a page-turner and a laugh-out-louder, with sweetness and romance and tartness and irony in perfect balance.

What a great book, seriously.

[Robin Sloan/MCD]