Instagram has a new leader in Facebook (FB) veteran Adam Mosseri, the company announced on Monday — a plum role awarded to one of Mark Zuckerberg's most trusted lieutenants.

Mosseri has worn several hats at Facebook over the last nine years. He oversaw the team behind Facebook's ever-popular News Feed for nearly six years and during several pivotal moments in the social network's history. Those moments include the 2016 presidential election when the social network faced the uphill battle of cleaning up the News Feed to clamp down on disinformation.

"Adam is the real deal: a thoughtful leader and smart about product," a former colleague of Mosseri tells Yahoo Finance. "He also has great brand and community instincts. I think he's perfect for this role."

Mosseri replaces longtime chief executive and co-founder Kevin Systrom, who abruptly announced his departure last week, alongside co-founder Mike Krieger, who had served as Instagram's chief technology officer for eight years. The co-founders did not give a specific reason for resigning, but the moves reportedly come after months of internal squabbles over product changes, staffing changes and Mark Zuckerberg's increasing control over Instagram.

Raised in Chappaqua, New York, the French-speaking Mosseri attended Horace Greeley High School with his brother, Emile, now a musician in a New York rock band called The Dig, before majoring in Information Design and Media at New York University. He co-founded the architectural firm, Blank Mosseri, before doing short stints as an adjunct professor at the Academy of Art University and a product designer at TokBox, a live video startup.

A self-proclaimed avid cook, Mosseri currently lives in San Francisco with his wife Monica, a business partner at an interior design firm, and his two young sons, Blaise and Nico, where they are active in local causes, including The Shanti Project, a non-profit that offers services and support to individuals with life-threatening illnesses. He joined Facebook in 2008 as a product designer before working on several of the social network's most prominent projects.

A member of Zuckerberg's inner circle

Although Mosseri is considered a member of Zuckerberg's inner circle at Facebook, it hasn't always been smooth sailing for him at the social network.

Before working on News Feed, Mosseri served as project manager of Facebook Home, a now-defunct user interface launched on some HTC and Samsung smartphones back in 2013 that let users quickly launch apps, receive Facebook notifications and send Facebook messages. But Facebook Home earned mixed reviews and never became the ubiquitous fixture among Facebook users Zuckerberg wanted it to be.