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Exclusive: Slack Promotes April Underwood to Chief Product Officer

April 4, 2018, 12:00 PM UTC

Slack is promoting VP of product April Underwood to be its first-ever chief product officer, per an announcement from CEO Stewart Butterfield, first shared with Fortune.

The move comes on the heels of Butterfield’s appointment of long-time insider Allen Shim as the company’s first CFO, which was announced in early February. This was soon followed by yet another appointment: former Goldman Sachs exec Edith Cooper was named the enterprise collaboration darling’s second independent board director. (Its first independent director was Square CFO Sarah Friar, who joined the board last year.)

Underwood’s promotion means expanded responsibilities for the exec, including overseeing the company’s design team and its “Search, Learning and Intelligence” group, a New York-based division tasked with rolling out artificial intelligence-powered features on Slack. But significantly, it is also yet another sign that the startup, currently valued at about $5.1 billion, is growing up—and inching its way toward an initial public offering.

“We are maturing as a business,” Underwood said in a phone interview with Fortune. “We’ve had an incredible amount of consistency on our executive team.” (The newly-appointed CPO also noted she had “nothing to share” regarding possible timing of an IPO.)

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The new title marks Underwood’s third promotion since she joined Slack in 2015, initially as head of platform. Prior to Slack, the long-time techie had done stints at Twitter and Google. (Another note on the timing of her promotion: Underwood came back to work just last week, after taking maternity leave.)

Slack has changed drastically in the last three years, and not just when it comes to its ballooning valuation. Six months after Underwood joined the company, her team launched Slack’s “platform,” which includes a series of software tools that allows third-party developers to offer up their apps to its users. Today, the company says that about 90% of the paying customers on Slack are actively using the more than 1,000 apps available through the platform, including productivity offerings like Trello and Asana.

In addition to the breadth of tools available on Slack, both homegrown and those developed by third parties, the company’s customer base has also expanded. About 50,000 of the “teams” using Slack are paying customers; the company’s total number of weekly active users is 9 million. And while many early Slack devotees were comprised of tech industry workers, that makeup has now changed significantly. “We have a more diverse set of customers than we’ve ever had before,” Underwood told Fortune. “These customers include companies from Liberty Mutual and Target to dairy farms.”

One of Underwood’s responsibilities is making sure that, even as Slack evolves its product lineup and adds more features that appeal to a wider swath of users, it maintains the same look and feel and ease of use of the original offering. According to Slack CEO Butterfield, that’s a continuation of what she’s already accomplished at the company: “April has been instrumental in getting Slack to where it is today, and I know she is going to be instrumental in taking us to the next level as well.”