Slack has purchased Astro, the maker of an email app with a built-in smart assistant that helped sort through your messages and elevate important items to your attention.

It may seem curious for Slack, the giant chat app with the goal of killing email, to buy an email app — but the pairing makes a good deal of sense. Astro’s focus was on business users, and it built out some smart integrations inside of Slack. With the two teams combined, Slack can use Astro’s experience to build a native solution for dealing with emails right inside the chat app.

There is some bad news, though: Slack is shutting down Astro’s email app. The app will stop functioning on October 10th. That’s unfortunate, given that good third-party email clients have become increasingly hard to come by, and Astro had some features that really made it stand out.

“We’re in a position to make that interoperability [with email] much simpler and much, much more powerful.”

The fact that Slack is shutting down Astro’s app makes it pretty clear where this acquisition is going. It seems less like Slack plans to launch an email app of its own and more like Slack plans to include ways to work with your email inside of its chat app. That could include basic email management, but the real key would be features that let you collaborate on email — so using a chat thread instead of a Reply All chain for internal messages or directing a customer support message to the correct Slack channel to be answered right there.

Slack hasn’t actually announced any specifics yet, but it does hint that this is the direction it’s headed. “We’ve taken some steps to make it possible to integrate email into Slack, but now we’re in a position to make that interoperability much simpler and much, much more powerful,” the company writes.

Both Slack and Astro had a focus on business users, and they’ve been particularly cognizant of supporting third-party services like Salesforce, which businesses use to manage interactions with customers. Salesforce and similar services could already integrate with Slack, but they’re often based around email. And since email isn’t really going away, Slack is instead trying to bring the experience inside its chat app to make it more manageable.

There’s no timeline on when any of these email features will start coming to Slack. But with Astro’s team on board, it’s clear they’re a priority.