Amazon announced Tuesday that founder and CEO Jeff Bezos, who has led the company from a small dot-com startup to one of the largest companies in the world, will be stepping down in the third quarter of 2021.

Bezos will be replaced by current AWS CEO Andy Jassy, an appointment that now opens up the top spot at the nation's premier cloud vendor. Bezos, however, will still serve as executive chairman of Amazon's board, which gives him an outsized role in continuing to lead the company he started in 1995.

"Andy is well known inside the company and has been at Amazon almost as long as I have. He will be an outstanding leader, and he has my full confidence," Bezos wrote in an email to employees. While Jassy runs Amazon, Bezos said he'll be focusing on other projects: "the Day 1 Fund, the Bezos Earth Fund, Blue Origin, The Washington Post, and my other passions."

Jassy, who was appointed AWS CEO in 2016, helped establish the entity as the world's biggest cloud provider. But competition in the space, namely from Microsoft, is heating up. Revenue at AWS rose to $12.7 billion in the fourth quarter, slightly below what Wall Street expected. Microsoft doesn't disclose Azure revenue as a standalone metric, but the "Intelligent Cloud" business, which includes cloud and other business segments, reported nearly $15 billion in revenue in the latest quarter, including a 50% jump in revenue from Azure, per the company.

Alongside the leadership transition, Amazon reported a 44% jump in revenue in the three months through December to $125.6 billion. In 2020, overall sales increased a jaw-dropping 38% to $386 billion.