Slack is a chat app that lets robots speak to humans

Stewart Butterfield (left) has gone from photos to video games to chatrooms.
Stewart Butterfield (left) has gone from photos to video games to chatrooms.
Image: Wikimedia Commons
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After making and shutting down Glitch, a critically admired but commercially unsuccessful game, Flickr co-founder Stewart Butterfield’s Tiny Speck is making the most of its second act. The company announced Friday that it had raised $42.5 million to grow its popular communications application, Slack. The funding was lead by the Social + Capital Partnership, making its biggest ever investment.

The service, based on hacks that the company’s game developers used to improve their productivity when using online chat to communicate, publicly launched just 10 weeks ago. What distinguishes Slack—and has earned it good reviews in the tech industry—is its ability to integrate chat with automated alerts and information delivered by ”bots.” (Data and alerts from external services pop up in chat streams, and users can also easily program the software robots to reply when a user types a specific keyword.)

The service is intuitive, highly functional, and even has a sense of humor. (The internal error page admits to a sense of “self loathing” for asking you to refresh your browser.) We spoke to Butterfield in March, and he outlined then why he thinks Slack works so well, particularly for the technical community and developers, which have been the biggest early adopters. That includes teams at big firms such as Adobe, as well as startups like Rdio and Medium. Overall, there are 60,000 daily users.

Slack creates searchable chat streams for entire teams, small groups, and individuals in one window, and integrates a wide variety of other services. It also syncs across desktop and mobile devices. Competitors include HipChat, Yammer, and Campfire, as well as newer companies like Convo. Slack is currently free (and plans to remain so), though to archive and search more than 10,000 messages requires a premium subscription.

Most office workers, especially those in the knowledge industry, feel overwhelmed by the sheer number of communication services we use, including email, instant messaging, social media, and project management software. And as soon as we stand up from our desks, that tangle of communications transfers to our mobile devices. But the modern technology worker has it even worse—many of those communications aren’t even from humans, and those often require quick response.

“You get live alerts from application performance-monitoring software, crash reports from mobile apps, alerts from continuous integration testing tools, all that kind of stuff—on top of feedback coming in in real time via Twitter and customer-feedback forms, along with competitor information,” Butterfield says. “There’s just a huge volume of data.”

In Slack, one of these automated alerts—a customer support ticket from ZenDesk, for example, or a request for help via Twitter—could show up in team’s group chat. That way, it’s right there for people to discuss and respond to quickly where they’re already working and talking.

By way of example, Butterfield said that there are about 2,000 messages a day written by humans in Slack at his company. Another 6,000 more are generated automatically by machines. With such a high volume of information, having it all in one place, ordered, highly searchable, and with human chat layered on top helps make a fragmented and overwhelming amount of communication easier to deal with.

And it’s not just for tech companies. The platform is also popular in newsrooms for many of the reasons developers like it—for helping organize long lists of links, interesting tweets, headlines, and the updates that are part of digital journalism. (Quartz’s staff uses it.)

Slack is certainly having its moment, and many will initially jump on the service because they’ve heard about a friend or competitor using it. What remains to be seen is whether this application will become a permanent part of offices’ communications infrastructure, instead of a brief experiment.

And while Slack seems to be gaining ground in the small companies or teams within companies that are using it, it remains to be seen whether the system can scale up for a company with hundreds or thousands of employees. To do that, it will probably need to develop new capabilities to communicate across teams, as well as enhanced security.