Square co-founder Tristan O’Tierney is dead at 35.
O’Tierney had been struggling with addiction and was seeking treatment.
O’Tierney created the first Square iPhone app and left the company in 2013.
Tristan O’Tierney, a co-founder of San Francisco payments company Square, died Feb. 23 in Ocala, Fla., of causes related to addiction, his family said. He was 35.
He is survived by his 3-year-old daughter, Rumi Ari; his girlfriend, Anjela Ramos; parents, Mark and Pamela Tierney; and sister, Terri Lynn Cloud.
His family is awaiting an official cause of death from officials.
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“I do know that it was in relation to his addiction,” Pamela Tierney said. “I know he got to the hospital, he couldn’t breathe and they couldn’t revive him.”
O’Tierney was in a three-month rehabilitation program in Ocala and had been battling addiction for three years, Tierney said. O’Tierney openly discussed his struggles with addiction on social media. “As some of you may know, I’ve been battling with addiction for these past few years,” he wrote in September in a now-deleted Instagram post that he also shared on Twitter. “With some success. A lot of failure too though.”
Born on a naval base in Adak, Alaska, O’Tierney grew up in different states before settling in New York. He attended Rochester Institute of Technology from 2001 to 2008 and graduated with a degree in computer science. He first came to the Bay Area in 2005, when he worked as a software engineer at Yahoo. He went on to hold positions at Apple, VMware, and Tapulous.
Jack Dorsey and Jim McKelvey hired O’Tierney to develop Square’s original mobile payment app in early 2009, and O’Tierney is generally credited as a co-founder. He left the company in 2013. Square, which now has almost 2,000 employees, declined to comment. The company’s website does not mention O’Tierney.
“I will really miss him and want his memory and legacy to last,” said Dom Sagolla, a former associate of O’Tierney who was also briefly his roommate. He noted that O’Tierney also helped develop the official iPhone app for Barack Obama’s 2008 presidential campaign. Sagolla, who worked with Dorsey at a podcasting software company, Odeo, which gave birth to Twitter, said he introduced Dorsey and O’Tierney in 2008 at an iPhone-app development event he organized.
A 2014 Business Insider article reported that Dorsey had originally hired O’Tierney to work on a different project called Log, a private journal-keeping app, before they turned their attentions to Square, which was initially called Squirrel.
Many Square colleagues shared memories of O’Tierney on Twitter after learning of his death.
Pamela Tierney said she visited her son in rehab two months ago, and the two took a glass-bottom boat ride up a river to see some greenery and alligators.
“We had a great time. He was so happy and always so bright,” she said. “We thought he was doing so good. We just kept hoping and hoping.”
Tristan O’Tierney had battled addiction for the three years, his mother said.
Photo: Courtesy Tierney family 2009
O’Tierney’s Instagram account showcased his talent for landscape photography, a passion he embraced after leaving Square to travel the world.
The spelling of the family’s last name is different because his parents, who are now separated, wanted O’Tierney to have more of a marker of their Irish heritage.
A memorial service will be held in San Francisco in the next two to three weeks, the family said.