In the land of geekdom, Paul English walks among idols. After all, he's the guy who co-founded kayak.com in the early 2000s — then sold it for a cool $2 billion. But for a keyboard Luddite like myself, he was one more unknown in the unknowable world of digital technology.

In "A Truck Full of Money," award-winning author Tracy Kidder makes some sense of that world with a portrait of English — a blue-collar kid who stumbles onto an innate genius for binary language. It starts when English hacks into a teacher's gradebook, and ends … well, his story is still being written, not unlike the code he so magically imagines and the start-ups he is driven to launch.

English is largely self-taught and is usually the fastest and most inventive programmer in the room. But just as coders are finding the power of their cursors, he peeks out at the bigger world and sees big problems to solve — and big money to be made. As Kidder writes: "He had a mind for the age that was coming. He stood on the right rung of the evolutionary ladder."

In Kidder's depiction, English isn't always likable. He has little patience for those who can't keep pace. He can be arrogant; when he pitches vague ideas to investors, he makes it clear he's selling himself — and they would be losers not to buy. He can be reckless with money. And he often shrugs off treatment for bipolar disorder in fear of losing "the fire" — hypomanic phases when he is most creative. In both business and personal life, he honors the frenetic entrepreneurial mantra: "Fail fast and pivot." Snippets of his e-mails help reveal a complex character who, for all his openness, remains enigmatic.

But Kidder paints with a respectful brush. English is loyal to partners, students and his native Boston. To honor a mentor, he vows to give away his fortune before he dies. He makes nighttime visits to the homeless, where he has an epiphany: For all the money and imagination he can throw at a problem, sometimes the better fix is as immediate — and real — as a pair of clean socks. At book's end, he is onto his next "killer" idea while doing stints as an Uber driver in his Tesla, talking to real folks about their real lives, probing for real and immediate solutions.

Kidder is no trickster as a writer. There are no breathless cliffhangers, gotcha scandals or sex-steamed detours to make this a late-night page-turner. Rather, his work builds on a deep fascination with — and access to — an insider's world. Readers willing to follow him will "grok" those worlds in ways they hadn't before.

Tracy Kidder

Kidder is on familiar ground here, weaving themes of technology, philanthropy and human obsession found in his Pulitzer Prize-winning "Soul of a New Machine" and bestselling "Mountains Beyond Mountains." And he delivers his signature strength, which stitches extraordinary people into the context of their times.

Jacqui Banaszynski is a Pulitzer Prize-winning reporter who teaches at the University of Missouri School of Journalism and coaches writers worldwide.

A Truck Full of Money
By: Tracy Kidder.
Publisher: Random House, 259 pages, $28.