Sam Trabucco got rich trading crypto. Now he’s the odd man out in the FTX saga.

Like other entrepreneurs who reach success at a young age, Sam Trabucco got a taste of the high life.

He bought a yacht and a multimillion-dollar condo overlooking the Golden Gate Bridge, and partied with his friends in Las Vegas and the Bahamas last year.

Then, just ahead of his 30th birthday, he walked away from his high-level job at Alameda Research, the trading firm associated with crypto exchange FTX — right before the whole thing collapsed behind him.

Trabucco was one of the top executives in Sam Bankman-Fried’s crypto empire. He served as co-chief executive of Alameda until August. In November, FTX and Alameda imploded in a matter of days as a run on deposits exposed that Alameda had lost billions of dollars in FTX customer funds.

Now, the companies are the subject of bankruptcy proceedings and a sweeping criminal investigation, and several of Trabucco’s former colleagues have been charged with fraud. Authorities allege Bankman-Fried orchestrated the scheme, in which Alameda used FTX customer funds to prop up its trading and to make loans to executives, among other things. Bankman-Fried has pleaded not guilty.

Investigators have accused FTX cofounder Gary Wang and former Alamedaco-CEO Caroline Ellison of fraud and other violations. Ellison and Wang agreed to plead guilty in late December and have been cooperating with investigators.

Trabucco, by contrast, has not been as prominently featured in the legal proceedings as his former colleagues. He has not been charged, nor is it known publicly if he is cooperating with investigators.

Neither Trabucco nor members of his family would comment publicly.

A Globe review of his public interviews, property records, and social media posts from him and his friends, as well as interviews with a half-dozen acquaintances, reveals Trabucco was similar to his FTX and Alameda peers, but also different in important aspects.

On one hand, Trabucco and the other principals showed immense mathematical talent as kids and attended prestigious schools. Long before they worked together, Trabucco, Bankman-Fried, Wang, and Ellison crossed paths in competitive math circles.

But Bankman-Fried and some of his lieutenants were also devotees of “effective altruism,” a charitable movement that encourages successful people to use their wealth to do as much good as possible.Trabucco, on the other hand, had a more classic motivation: Crypto was a way for him to make a lot of money.

Trabucco grew up in Natick and attended Roxbury Latin School, a private boys high school. The son of a Wellesley College campus police officer and a preschool teacher, he referred to himself in video interviews as “one of those math kids” who enjoyed solving puzzles more than playing outside.

He took part in math competitions, sometimes against Ellison, who attended Newton North High School. For two summers he attended Mathcamp, a highly selective five-week program designed to expose high school students to advanced math concepts.

At Mathcamp, Trabucco overlapped with Wang in 2008, the summer before their sophomore year of high school, and he first met Bankman-Fried there in 2010, when the program was held at Mount Holyoke College.

“When I realized I was good at math, even back when I thought the outcome there was, ‘Oh I could win math competitions,’ I really went crazy for that,” Trabucco said on one podcast. “Almost to the detriment of most other skills that I could have been developing in my life.”

He went on to study mathematics and computer science at the Massachusetts Institute of Technology, where Wang was in the same class and Bankman-Fried a year ahead of them. Bankman-Fried graduated in 2014, while Trabucco and Wang graduated in 2015.

After college, Trabucco, Bankman-Fried, and Ellison, who graduated from Stanford University with a degree in math, worked at quantitative trading firms. Trabucco moved to Philadelphiaand joined Susquehanna International Group, where he had an internship during his junior year.

“Alumni of math programs in general, Mathcamp included, often end up in finance or lucrative careers,” said Daniel Zaharopol, chairman of the Mathcamp board of directors.

Then crypto caught his eye. Trabucco began to trade cryptocurrency with his own money and sawan opportunity for arbitrage trading, which involved buying and selling crypto on different markets, profiting on the price difference.

Trabucco admitted he “didn’t really have any strong opinions about the technology or whether crypto made sense.” For him, it was about the opportunity to get rich.

“I was really just … finding it irresponsible not to be focusing on [crypto] when I could be making more money doing that than anything else I was aware of,” he said during a video interview in 2021.

Trabucco left Susquehanna in 2017 and moved to San Francisco. Bankman-Fried started Alameda Research that year, and at some point the two had dinner, which led to Trabucco joining the firm as a trader.

One former Alameda employee said Trabucco was a “reserved person in general but felt comfortable in the office.” They said he was passionate about things such as trading, numbers, trivia, and crossword puzzles. (Some of his puzzle submissions were published by The New York Times.)

“Some of us would get together and attempt to solve his crossword puzzles,” the former employee wrote in a message to the Globe.

Math was a big part of the work culture of Alameda. Traders tried to assess the “expected value” of different scenarios, picking the one with the most lucrative likely outcome, no matter how big the risk.

But there was another big idea in the minds of some Alameda and FTX leaders: effective altruism, which in their world meant using evidence and reasoning to figure out how best to help people. Bankman-Fried publicly talked about wanting to give away most of his fortune to charitable causes that could benefit humanity. Ellison wrote on her now-deleted Tumblr blog that “money is too easy. … Making the future look the way I want it to really seems like the only worthy goal.”

Effective altruism could mean, for example, providing medical supplies to a developing country where a particular disease runs rampant or donating only to organizations that have a demonstrated record of bringing about positive social change.

By all accounts, Trabucco wasn’t interested in theeffective altruism philosophy and didn’t participate in it. He got into crypto to make money for himself. And that he certainly did.

In 2020, he bought a four-bedroom house in Wells, Maine, for$500,000, where it appears his parents now live. The next year he purchased a 3,800-square-foot luxury condo in San Francisco with views of the Golden Gate Bridgefor nearly $9 million. Trabucco also bought a 52-foot boat and named it “Soak My Deck.”

The former Alameda employee saidit didn’t appear Trabucco was in Bankman-Fried’s inner circle, which included Ellison, Wang, and Nishad Singh, FTX’s former director of engineering. This group also started the FTX Future Fund, the now-shuttered charitable arm of FTX, without Trabucco.

“I assume these 4 shared things among each other which weren’t shared with Trabucco,” the former employee wrote to the Globe.

Nevertheless, Trabucco and Ellisonwere promoted from traders to co-CEOs of Alameda in the fall of 2021. Both lived in Hong Kong, where Alameda had relocated, and also spent time working in the Bahamas, where Bankman-Fried and FTX were based.

Trabucco and Ellison have said publicly that FTX and Alameda operated as separate companies, though they were both owned by Bankman-Fried.

“To be clear, I work for Alameda, not FTX,” Trabucco said in a video interview, weeks before his promotion. “They’re both founded by Sam Bankman-Fried but, yeah, completely different.”

However, prosecutors said Alameda received special privileges on the FTX exchange, which gave it the ability to borrow “a virtually unlimited” amount of money, among other benefits.Investigators have accused Alameda of using billions of dollars in customer funds from FTX to repay its own loans to other lenders, as well as lend money to executives.

In her plea hearing, Ellison admitted she knew about the arrangement and helped facilitate it.

During his final months as co-CEO, Trabucco surrounded himself with friends and traveled.

In the spring of 2022, former MIT classmates visited him in the Bahamas. In July, he went to Las Vegas during MIT’s Mega-Pi, a reunion held 3.14 years after graduation that combined multiple classesbecause of the pandemic.

In October — two months after he stepped down from Alameda —Trabucco went back to the Bahamas for his 30th birthday, celebrating with a cake that had his face printed on it, according to his friend’s Instagram account.

That was one month before things would go haywire at Alameda and FTX. And since the collapse,Trabucco has been off social media and hasn’t spoken publicly.

“Much love to everyone,” Trabucco wrote in his last Twitter post on Nov. 8, as the FTX saga began unfolding. “I’m sure the past few days have been dark for many and I hope the road ahead is brighter.”