Jeff Wilke, CEO of Amazon’s worldwide consumer division, is planning to retire in the first quarter of 2021, the company announced in a regulatory filing on Friday.

Wilke oversees several of Amazon’s high-priority business lines and was considered a possible successor to CEO Jeff Bezos. The Pittsburgh native (and Steelers fan) joined the company in 1999 and helped build Amazon’s logistics operations into the behemoth it is today. He was put in charge of the company’s global consumer business in 2016.

He said in a memo to staff on Friday that it was “time for me to take time to explore personal interests that have taken a back seat for over two decades,” according to The Wall Street Journal, adding that he was focused on preparing Amazon for the upcoming holiday shopping season.

Bezos said in an email to employees that Wilke had set up the company to succeed in his absence, referring to him as a “tutor.”

“Jeff’s legacy and impact will live on long after he departs,” Bezos wrote. “He is simply one of those people without whom Amazon would be completely unrecognizable.”

Wilke is among several top Amazon execs who have recently announced they’re leaving the company. Vice president of robotics Brad Porter announced last week that he is leaving to join an AI company. Peter Vosshall, a distinguished engineer on Amazon Web Services, retired in February, and Paul Viola of Amazon’s Air division left earlier this year as well.

Dave Clark, Amazon’s senior vice president of retail operations, will succeed Wilke. According to a Bloomberg profile from last year, Clark has a reputation for visiting Amazon warehouses to assess whether people were working hard enough, which earned him the nickname “The Sniper.”