One of the top engineers in Walmart’s global tech team, Michael Pfaffenberger, has quit the retail giant after completing a nearly five-year stint. As the creator of Walmart’s internal vibe-coding, AI-powered tool called Code Puppy, the leading executive mapped out the journey ahead and bid farewell to his colleagues in a memo, according to Business Insider.
Pfaffenberger, who climbed multiple ranks over his more than four-year career at Walmart, is leaving the company a year after his flagship AI-driven creation grew from 1,000 users to more than 75,000 and has gained much attention among non-engineers as well. Business Insider further reported that the company had also confirmed the distinguished engineer’s exit and “wished him the best”, as he’s set to join artificial intelligence startup Pydantic.
The major shakeup comes weeks ahead of Walmart’s earnings report on August 20. Pfaffenberger’s departure adds to the list of recent leadership changes at the US retail chain months after John Furner assumed the CEO role in February. In May, CNBC reported that Tom Ward, the chief operating officer of Walmart’s warehouse chain Sam’s Club, was retiring, and Cedric Clark, Walmart’s executive vice president of US store operations, was quitting the business.
Walmart AI engineer quits to join Pydantic
“I’m filled with joy that I was able to create software that improved the lives of so many folks at work and outside of it,” Michael Pfaffenberger wrote in the memo, as quoted by Business Insider. “These decisions are never easy, but the time is right.”
As he announced his departure from the company, the AI engineer confirmed that his creation, Code Puppy, was “staying” and its operations would be supported by his colleagues. He event listed all those who would continue building on the projects: Ryan Eccles – Associated Fellow II, John Choi – Principal Software Engineer, Kaveri Bakshi – Director, Technical Program Management, Wesley Blakemore – Senior Software Engineer, Andrew Tilson – Principal Software Engineer and TJ Webb – Principal Software Engineer.
Admitting that the career switch was “not easy,” Pfaffenberger wrote, “I poured my soul into it for the past year. You kept me motivated. All of you, the users who felt empowered by the tool that I created, have been a lifeline and the reason I’ve kept going for so long.”
The Code Puppy creator also confessed that he wrote the “tenets” on the Walmart website defining the project’s identity already knowing that he would be gone soon and that the rest of his team would have to keep it alive.
“Now that the team is up and running, I must say goodbye,” he added.
“The decision to open source Code Puppy was pivotal. Code Puppy has been downloaded on the open source over 496,000 times, including 71,000+ times last month, by users all over the world. Dozens of individuals unaffiliated with Walmart have contributed powerful features and bug fixes. Because of this, it was almost like I had an entire team of elite software engineers – some of them folks at the absolute top ofde their fields, coming out of Stanford, like Qian Li (Founder of DBOS),” the memo went on, as quoted by Business Insider.
Starting his Walmart journey in 2021 as the principal data scientist, Pfaffenberger gradually experienced a role change as he took on the duties of the principal software scientist. According to his LinkedIn, the ex-Walmart veteran said that the “role change” didn’t necessarily invite any “real job change, but he noted that the “role fits my activities better as I’m more hands-on with systems building these days than research / more scientific work.”
Last year, he received an “in-seat promotion.” Becoming the ‘Distinguished Software Engineer,’ his new role demanded a “new focus on Agentic AI platforms and applications within Walmart Global Tech’s Transaction Systems division,” as per his LinkedIn.
As a computer science graduate from Virginia Commonwealth University, the Walmart alum has held multiple senior positions at Capital One, Snag and S&P Global in the past.
Now that he’s headed to Pydantic, the AI startup’s CTO, David Montague, hailed the upcoming transition in a statement to Business Insider, praising Pfaffenberger’s experience at a large enterprise building an AI tool coordinating multiple agents as a critical skill.
More about Michael Pfaffenberger’s creation Code Puppy
Walmart’s viral internal AI coding tool is a lot like Anthropic’s Claude Code and OpenAI’s Codex in the sense that it also builds features, fixes bugs and analyses projects. However, unlike most rivals, Code Puppy doesn’t rely on a single AI model or provider, as it has the capability of working with dozens of models from different suppliers. As a result, developer cane switch between them, compare results or even use several at once.
Walmart already has several agents, but Code Puppy is especially praised for helping workers, from software engineers to hourly forklift drivers, across the company code their own software tools and solutions.
At the annual shareholders meeting last month, Pfaffenberger and his co-worker John Choi were honoured for their contribution to the project, with Walmart CEO John Furner presenting an award to them.
Describing its use further, chief technology officer Suresh Kumar said in June: “People are using it in merchandising, people are using it in supply chain, store managers are using it. It’s a way where the power of technology has now gotten democratised.”