Hector Rivas spent a decade building ThriftBooks into one of the country’s largest used-book sellers, before an unlikely second act: co-founding a sports agency representing NFL players.
That career change led him to the problem behind his newest startup, and to the Las Vegas Raiders running back who just invested in it.
Nukleus, based in Issaquah, Wash., is building what Rivas calls an operating system for the business of sports. The idea is a single workspace for everyone in an athlete’s orbit: agent, lawyer, CPA, financial advisor, marketing team, and others. It lets them all work from the same contracts, deadlines and records, rather than each keeping a separate pile of emails and spreadsheets.
The idea came out of Rivas’s years at Disruptive Sports, the agency he co-founded in 2020 and left earlier this year.
Ashton Jeanty, who signed a four-year, $35.9 million rookie contract with the Raiders in 2025, has taken equity in the company and signed on to serve as its public face.
Nukleus has also named four strategic investors: Mat McBride, Microsoft’s executive vice president and CFO for commercial products and infrastructure; WaFd Bank President and CEO Brent Beardall; investor Skyler Nelson, previously of Vulcan Capital and its successor firm Cercano; and Dr. Brett Kindle of the Andrews Institute in Gulf Breeze, Fla.
The company has a team of 12 based out of its Issaquah office, plus a supporting engineering team in India. Most of the team is engineering.
Other executives include CTO Eric Ahlstrom, previously at Microsoft, Unity, Oracle and ESPN; chief creative officer Ben Miller, a former creative director at the University of Washington and CAA Sports; and CFO Matt Porter, who worked with Rivas at ThriftBooks, EcoGoodz and Disruptive.
Nukleus closed a pre-seed round from friends and family in 2025 and is raising again now. Rivas declined to disclose the amount raised by the company so far.
From books to football: Rivas was ThriftBooks’ first CEO, running the used-book seller for about a decade after it launched in 2003. Based in the Seattle area, the company grew during his tenure from a storage unit in Kirkland, Wash., to 10 distribution facilities in 10 states, by his account.
He went on to found EcoGoodz, a used-goods and overstock brokerage, and in 2020 co-founded Disruptive Sports Agency with agent Henry Organ.
Rivas, an NFLPA-certified contract advisor, worked the business side of the agency. He left earlier this year to build Nukleus full time.
The years inside the agency are what produced the idea.
Everyone in a player’s orbit was working off “their own version of the truth,” Rivas explained via email: the agent, the lawyer, the CPA, the financial advisor, the marketing team. The athlete, he said, “was the one absorbing the cost of that disconnect,” in slower decisions and deals that fell through the cracks.
The pitch in Las Vegas: Jeanty and Rivas knew each other from Rivas’s years at the sports agency, and Rivas said the running back had been tracking what he was building.
“Because Ashton and I already knew each other, and he’d been aware of what I was building, the conversation came together naturally,” Rivas said.
He flew to Las Vegas to walk Jeanty through the model, the team, and where the company was headed. Rivas said Jeanty’s equity reflects both money invested and his role promoting the platform.
In a statement, Jeanty described the job of running his own career.
“Coming into the NFL, you become a CEO, directing a team of agents, advisors, and marketers, whether you’re ready or not,” he said. “Nukleus is what finally gets them all on the same page, so I can actually run that team the way it should be run. That’s why I invested in it.”
Where things stand: The product is in a free beta with about 30 users, including athletes, agents, agencies, lawyers and marketing staff. Nukleus plans to charge $99 per user per month for a starter plan and $249 for a full-featured one, with custom enterprise pricing. Athletes join free.
Alongside contract storage, deadline tracking and a shared workspace, the company is building AI tools meant to answer questions about contract terms and league rules.
Others are working similar territory. Agent Live 360 sells software built specifically for sports agents, and Opendorse, which says it works with more than 1,000 sports agents, offers tools to negotiate, approve and track deals. Nukleus says it differs from narrower tools by serving everyone in an athlete’s orbit.
The bigger bet: The company is looking well past a single app.
“Long-term, I don’t see this as a tool athletes use, I see it as the infrastructure the entire business of sports runs on,” Rivas said. “Every athlete becomes the center of their own connected team, and every professional working with them, across every sport, at every level, operates on one shared system instead of a hundred disconnected ones.”
