When Brian Mosdell got a call “out of the blue” from SpaceX, he wasn’t sure what to think. He had a safe, comfortable job at the United Launch Alliance, and like many there, he didn’t think SpaceX was a serious player. “I thought they had a PowerPoint and paper rocket,” or one that just existed in theory, he said. His colleagues at the Alliance wondered why, in 2008, he’d want to go work at a company like SpaceX, which had accomplished relatively little. “Like me, they didn’t see any threat coming out of SpaceX,” he said. Or any future.

But when he went out to California for his interview, “everything really changed my mind,” Mosdell recalled. “I saw at least $25 million of flight hardware in various stages of fabrication. That’s when my head snapped and I said, ‘Hey, wait a minute. This is the real deal.’”

In interview after interview, the executives stressed that SpaceX was different than any of the companies listed on his resume. “This is not heritage aerospace,” he was told. “We’re lean and mean. If you come work for us, you’re going to have a lot of creative license. You’re not going to get stifled by bureaucracy.”

The corporate culture was freewheeling and hard charging, with a mix of industry veterans and young kids with virtually no experience in building rockets, but who were brilliant and willing to devote themselves to the cause with abandon.

It wasn’t a place for everyone. The whole enterprise of building rockets seemed a little crazy. The hours were ridiculously long; the work, challenging. It was great for young, energetic, and brilliant workaholics, but not so great for those seeking a “work-life balance.” Elon Musk was demanding and known to yell at employees on the middle of the factory floor. A former executive at Lockheed who got to know Musk and the culture at SpaceX couldn’t believe how relentless and demanding they were. “If I did that, at a public company, the HR person and the lawyers would be in my office within ten minutes to ship me off to eighteen months of sensitivity training,” he said.

Hans Koenigsmann, SpaceX’s vice president of mission assurance, praised Musk for the alchemy he performed at the company: “The way Elon turns the future into reality is pretty amazing,” he said. “The whole enterprise is pretty much against the odds.” But he also didn’t think he’d grow old at the company; he just didn’t have the energy. “It takes a toll on you, and it’s hard to do a half job at SpaceX.”

Musk was aware of how demanding he and SpaceX could be. “Some of the guys kind of got burned out,” he said. “They just got fried after too much intensity.”

Musk hired very smart people who had to prove their proficiency in personal interviews with him. Engineers stood atop the corporate totem pole, with everyone else behind. “SpaceX had what Elon called a high signal-to-noise ratio, meaning that people who added value were engineers. They were signal,” said Tim Hughes, the company’s general counsel. “And people who were nonengineers for the most part were noise.”

One of the early hires was Mark Juncosa, who came to the company right out of graduate school, lured by Musk’s smarts and passion and the whole wild vibe of the company, which included Musk’s edict allowing employees to get up and leave meetings they didn’t need to attend. No questions asked.

“There were a lot of people that were quite bright,” said Juncosa, who would become the company’s vice president of vehicle engineering. “And not boring. They all had a big fire under their ass and were quite crazy.”

Juncosa wasn’t sure that the company would ever be successful. “How are we going to figure out how to make a spaceship that took an incredible amount of people in the sixties, when we didn’t have those resources?” he wondered.

But here they were “fighting our fucking hardest,” all following Musk, believing that he always “figures out how to make the magic happen.”

By the time Mosdell showed up, the company had moved into a new, bigger facility in Hawthorne, a former Boeing 747 fuselage factory not far from the Los Angeles airport. For an aerospace engineer, it was like Willy Wonka’s chocolate factory. Massive rockets were being built from scratch, long cylindrical cores stretching along the factory floor like the hulls of great ships. Engines—new, American-made engines—were being manufactured in-house. And hundreds of workers, many of them so young it seemed as if they should still be in college, fanned out across a floor humming with what Mosdell saw as a sense of let’s-get-it-done urgency.

The company often warned job applicants that their interview with Musk could be short and awkward because he might be multitasking through it, or take long pauses to think during which he said nothing for minutes on end. Mosdell found Musk a touch awkward and abrupt, but smart. Mosdell had showed up prepared to talk about his experience building launchpads, which, after all, was what SpaceX wanted him to do. But instead, Musk wanted to talk hard-core rocketry. Specifically the Delta IV rocket and its RS-68 engines, which Mosdell had some experience with when at Boeing.

Over the course of the interview, they discussed “labyrinth purges” and “pump shaft seal design” and “the science behind using helium as opposed to nitrogen.” Mosdell didn’t know whether Musk was testing his knowledge or genuinely curious. And then it was over.

“He abruptly said, ‘Okay, great, thanks for coming in.’ And spun his chair around and went back to his computer,” Mosdell said. “I couldn’t tell if it went well or not.”

When he was hired in 2008, Mosdell became SpaceX’s tenth employee at the Cape, and was put to work almost immediately, rebuilding Pad 40. Eager to show he could be resourceful, Mosdell and his team became the scavengers of Cape Canaveral, going around looking for leftover hardware as if they were on a treasure hunt.

So, the old rail cars from the 1960s that had once been used to ferry helium between New Orleans and Cape Canaveral became new storage tanks. “We took off the wheels and basically set them up on fixed pedestals,” Mosdell said.

Instead of spending $75,000 on new air-conditioning chillers for the ground equipment building, someone found a deal on eBay for $10,000.

In addition to recycling old material, they pushed back on regulations they saw as anachronistic leftovers from an earlier era.

When the company was told it would cost $2 million for a pair of cranes to lift the Falcon 9, for example, it questioned the price, wanting to know why it was so expensive. The reason was that the air force required the cranes to meet a series of safety requirements to prevent, say, a hook from suddenly dropping too fast. But modern technology had rendered many of those requirements, some decades old, unnecessary.

Mosdell and the SpaceX team lobbied the air force officials at Cape Canaveral, ultimately convincing them to strip out many of the old regulations that were driving up the price. They did, and SpaceX was able to purchase the cranes for $300,000.

When Mosdell worked for large defense contractors, “there was never a mindset or interest in reusing things,” he said. “Everything needed to be built from the ground up. It’s government contracts and government money.”

The rules were the rules, and the price was the price. No one questioned the cost, or the regulations, or the system. That’s how it was done. Until SpaceX. It had an altogether different mind-set, an obsession with finding ways to do things cheaply and efficiently, and an almost instinctive contrarian bent that questioned everything—the price, the rules, the old way of doing things. If Cape Canaveral and its leaders were the adults, SpaceX was the child, constantly curious, always asking why.

Cost drove lots of decisions, even how the company would build its rockets. Although some companies assembled their rockets vertically on the pad, that required what was known as a mobile service tower. They were giant structures that would surround the rocket while it was being built and then get wheeled away.

“Elon is, like, ‘That is the dumbest thing I’ve ever heard of ever,’” exec Gwynne Shotwell recalled. “‘Like, how expensive and inefficient is that?’” SpaceX built its rockets in its California factory “where it’s all clean and neat and nice anyhow,” said Shotwell. By building them horizontally, you reduce the risk of having employees as they work high off the ground, she explained.

In the same frugal manner, the Dragon spacecraft looks the way it does because it’s the simplest design.

“If someone says design a reentry capsule, and you give it to NASA or someone else, they are going to spend, like, a year designing its shape,” said Steve Davis, SpaceX’s director of advanced projects. “For us it was, the bottom is the diameter of the Falcon 9. Because it was on the Falcon 9. The top is the diameter of the [port where it would dock with the space station]. The design is now complete. That was it. Connect two lines.”

The rocket’s avionics were powered by a $5,000 computer instead of the much more expensive aerospace hardware. One employee even found a piece of metal in a junkyard that he thought might be used as part of the rocket’s fairing, the protective cone on the top of the rocket that shields the payload, such as a satellite.

Instead of using the straps that came with the module used for storing cargo, which NASA’s astronauts on the space station apparently found cumbersome, they found straps using a NASCAR design that the astronauts loved.

SpaceX even questioned the kinds of latches that were used in the lockers of the space station. Each locker required two latches, which each cost $1,500 and had twenty to twenty-five parts. At “SpaceX, we weren’t going to build that,” recalled John Couluris, of SpaceX mission operations. “One engineer was inspired—I think it was honestly in the men’s room—where he saw the latch on a stall, and we were able to make a locking mechanism out of that.”

Instead of $1,500, it cost $30. “It’s more reliable, and it’s easier to replace if it ever goes bad,” Couluris said. “The astronauts, not only did they love it, but they loved the story behind it because that shows the ingenuity.”

These were new and innovative and totally different ways of doing things than anything NASA’s leadership was used to. And it took some convincing that, though different, SpaceX’s approaches were still okay.

“The biggest challenge, I think, that we had in the execution of this was convincing NASA, every step of the way, that though we’re going to do business very differently, we’re going to get it right,” Shotwell said. “Because no one had experience doing this job the way we wanted to do this job. Unfortunately, the industry is frankly, I think, hampered—I’ve been doing this for thirty years, so I think I can say that—by cost-plus contracts. The incentive on a cost-plus contract is not to minimize cost, it’s to maximize effort. Our philosophy was not minimize effort, but optimize effort.”

NASA officials were, at first, flabbergasted. But SpaceX ultimately won them over with its scrappy, Silicon Valley ethos.

The article has been adapted from The Space Barons: Elon Musk, Jeff Bezos, and the Quest to Colonize the Cosmos by Christian Davenport. Copyright © 2018. Available from PublicAffairs, an imprint of Perseus Books, LLC, a subsidiary of Hachette Book Group, Inc.