The new CEO of Twitter is Parag Agrawal — a technologist who, until today, has been a relatively low-profile but key member of the company’s leadership team.

Dorsey, who co-founded Twitter in 2006, announced his resignation from the social media company Monday. Replacing Dorsey in the top job is Agrawal: a 10-year Twitter veteran who has been its CTO since October 2017 and is suddenly the company’s public face to Wall Street, its millions of users and advertising customers.

Dorsey, in a memo to Twitter staffers he posted publicly, said “my trust in [Agrawal] as our CEO is bone deep.”

“He’s been my choice for some time given how deeply he understands the company and its needs,” Dorsey wrote of Agrawal. “Parag has been behind every critical decision that helped turn this company around. He’s curious, probing, rational, creative, demanding, self-aware and humble.”

Twitter has credited Agrawal’s engineering work on its revenue and consumer platforms with helping turn around its audience growth in 2016-17. Under Dorsey, who had been CEO since 2015, the company focused on making Twitter easier to use and more engaging, and also improving the reliability and scalability of the overall service and its advertising stack.

Agrawal noted that there were fewer than 1,000 Twitter employees when he joined the company in 2011. As of the end of September 2021, it has more than 7,100 employees worldwide, up 33% year over year.

“The world is watching us right now, even more than they have before,” Agrawal, 37, wrote in his own email to employees (and posted to Twitter). “Lots of people are going to have lots of different opinions about today’s news. It is because they care about Twitter and our future, and it’s a signal that the work we do here matters.”

Agrawal’s appointment as CEO has already raised hackles in right-wing circles. In a 2010 tweet that was recirculated Monday, Agrawal wrote, “‘If they are not gonna make a distinction between muslims and extremists, then why should I distinguish between white people and racists.'” He was quoting a satirical comment by comedian Aasif Mandvi, who said it on “The Daily Show With Jon Stewart” in a discussion about NPR’s firing of Juan Williams over his comments on Fox News about fearing people in “Muslim garb.”

Conservatives also pounced on comments he made in a November 2020 interview with MIT Technology Review in which, in discussing efforts to fight misinformation, he said Twitter’s role “is not to be bound by the First Amendment.” Some conservatives believe, despite evidence to the contrary, that Twitter and other social media platforms demonstrate a bias against right-leaning figures and viewpoints. (Note that the U.S. Constitution’s First Amendment prohibits the government from restricting free speech — and does not apply to private companies.)

Here’s an expanded excerpt of Agrawal’s answer to the question of how Twitter tries to balance principles of free speech with the need to counter misinformation: “Our role is not to be bound by the First Amendment, but our role is to serve a healthy public conversation and our moves are reflective of things that we believe lead to a healthier public conversation.” He said Twitter’s challenge is to make sure the recommendation systems it is building lead to “a healthy public conversation that is most participatory.”

In the CEO role, Agrawal has his marching orders cut out for him. At its first investor’s day presentation earlier in 2021, Twitter said it expects annual revenue to grow more than twofold over a three-year period — from $3.7 billion in 2020 to at least $7.5 billion in 2023 — on the back of new products and subscription services. In addition, Twitter projected at least 315 million monetizable daily active users in Q4 2023, representing a compound annual growth rate of 20% from 152 million daily active users reported in Q4 2019.

Agrawal acknowledged that those are “ambitious goals” and told Twitter employees “our critical challenge is how we work to execute against [the strategy] and deliver results.”

As you would expect, Agrawal has suddenly gained thousands of new followers on his @paraga Twitter account: He had about 27,500 before his appointment as CEO was announced, and that has climbed to more than 130,000 as of this writing.

Before joining Twitter in October 2011, Agrawal worked in research at AT&T Labs, Microsoft and Yahoo, per his LinkedIn page. He holds a PhD in computer science from Stanford University and a bachelor’s degree in computer science and engineering from the Indian Institute of Technology in Mumbai. According to his Facebook profile, Agrawal is originally from Mumbai. His Stanford doctoral thesis, published in 2012, is titled “Incorporating Uncertainty in Data Management and Integration.”

“I recognize that some of you know me well, some just a little, and some not at all,” Agrawal wrote in his first memo as Twitter’s CEO. “Let’s consider ourselves at the beginning — the first step towards our future.”