Cisco Gave One 27-Year-Old an Unlimited AI Budget to Rewrite 98% of Its Legacy Code

November 2 — According to Fortune, Cisco president and chief product officer Jeetu Patel assigned a 27-year-old engineer the goal of using AI to refactor and rewrite 98% of the company’s legacy code within 24 months — and gave him an unlimited token budget.

Legacy code is source code tied to operating systems or technologies that are no longer maintained, or code embedded in modern software to stay compatible with old functions; it is usually written with outdated technology and lacks complete documentation, making it costly to maintain.

“I gave him unlimited tokens because he’s going to refactor the code,” Patel said. “So I said to him, go for it, do whatever you want.” “He” is Padmanabhan Krishnamurthy, whom Patel calls “Paddy”.

Krishnamurthy co-founded the real-time translation startup EzDubs in 2023; Cisco acquired EzDubs in 2025 and he joined the company. Despite being a former founder and CEO, Patel says he was at the time “buried deep in the organisation, doing peripheral work that didn’t matter much”.

The turning point came during a visit by Patel to Cisco’s San Francisco office, when the two had a long conversation. Krishnamurthy suggested that with a two-person team he could completely rewrite Cisco’s vast legacy code. Patel said that until then, even the most forward-looking AI experts on his own team had never proposed anything like it.

Krishnamurthy has set himself a four-week validation period; his ultimate goal is to complete the refactoring of 98% of Cisco’s legacy code within 24 months.

It is worth noting that 98% is at this stage a stated goal rather than a delivered result, and the reports do not disclose how much code has been changed so far or what the experiment has actually achieved.