SIGN UP NOW: We're talking with Slack cofounder and CTO Cal Henderson about how to set the technical vision for a rapidly growing company

• Starting Up is Business Insider Prime's new live interview series.
• The first episode is with Cal Henderson, cofounder and CTO of Slack. It's recording live Monday and will be available afterward.
• Sign up to get the link here.
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Sign up for a reminder of the live interview with Slack cofounder and CTO Cal Henderson here. The interview streams live at 2PM ET and 11AM PT on April 27th.

The operative word in the startup space is scale.

For investors to get the return they seek (and founders the exits they want), you need to grow the company. A priority should be scaling your underlying technology fast. Real fast. Real fast. So that the chart looks like, as they say in Silicon Valley, "hockey stick" growth.

For the first episode of Starting Up, Business Insider is speaking with Cal Henderson, a world authority on scaling. He's a cofounder and CTO of Slack, the enterprise chat app that became one of the fastest companies to ever attain unicorn status. He also literally wrote the book on it: "Building Scalable Web Sites."

Before Slack, he was the director of engineering at Flickr, the Web 1.0 photo-sharing platform acquired by Yahoo.

In this 40-minute conversation, available exclusively to Business Insider Prime subscribers, we'll be speaking with Henderson about what it takes to achieve sustainable high growth, both in your technology and your organization. We'll ask him how Slack, which famously grew out of an online multiplayer game, initially tested for and arrived at product-market fit. And we'll get his best practices for understanding complex systems, whether that's software code, investor pitches, sci-fi novels, or his beloved London Underground.

Starting Up is the new live interview show for Business Insider Prime subscribers hosted by deputy editor Drake Baer. Sign up for a reminder for the April 27 interview with this link. Following Cal Henderson of Slack, we have interviews with Steve Martocci of Splice and Milind Mehere of Yieldstreet.