You’ve probably heard at least a little about the email-killing collaboration startup Slack. If you haven’t yet, you will. The company recently passed 1.1 million daily active users, and a whopping $25 million in annual recurring revenue. Billed as a messaging app for teams to communicate and collaborate, Slack has quickly become (maybe) the fastest growing software startup of all time.

There’s no question that workplace communication is Slack’s sweet spot, enabling faster and easier internal collaboration between groups of all sizes. But there’s another use case Slack empowers, one that’s gaining traction and helping drive growth: hosting communities.

Rather than host a forum or digital community themselves, or use social media platforms to engage, many community managers are turning to Slack as a place to quickly and easily build tight-knit communities. But why Slack? We talked to the founders of a few Slack communities to figure it out.

Ease of use

Slack is famous for being quick to get started and simple to use. Building a community with Slack lets community managers get started without jumping through the technical hoops of building a new platform, or developing a new channel on a social network. It’s also simple for new users to understand how the platform works and how to use the product, placing the focus on interactions right away without spending time figuring out how to send messages or make posts.

Abdallah El Chami is one such community builder, using Slack to host the “Startup604” channel, an entrepreneurship group in Vancouver. Startup604 has grown into a thriving network and is a place for the Vancouver-based startup community to easily connect, interact, and share resources.

El Chami chose Slack primarily for the ease of use. “After using Slack for several projects, I was so impressed with how easy it was to collaborate especially between people or teams who normally wouldn’t have much contact other than being cc’d on the same email thread.”

This simplicity creates a frictionless community experience, leading to increased interaction. Startup604 relies on the platform’s ease of use to onboard new members, enable group and direct interaction, and enable collaboration. El Chami: “The mix of user experience (minimal friction points), integrations, design (it’s nice to look at) and uniformity between platforms is what makes it take off.”

Exclusivity

Ginny Torok of Traackr is another community builder using Slack to connect people and create conversations. As an influencer marketing platform, their intent is to build an exclusive community of influencers, where prominent individuals can feel comfortable interacting with their peers.

Torok’s channel is tight-knit, focused on providing unique value to a community of influencers. In her words, “[Slack is] the easiest way to bring influencers together. I wanted to create a space to be able to provide influencers with value. So, the space is created as a way to connect like-minded influencers, and provide value for them. There’s a section to be able to get resources for content, like ask each other for quotes or input, and the team also provides a space to share news and knowledge.”

Slack enables Traackr to develop a private community, which has huge value for the individuals Torok is targeting. Torok: “It feels more private or exclusive than a LinkedIn group (even if it were a private group), which allows for more sharing and interaction. Influencers will be more likely to ask each other for input on content or quotes etc, in an exclusive Slack group.”

This sentiment is echoed by Luiz Centenaro, who quarterbacks customer success for Experiment Engine, a community-driven conversion rate optimization platform for brands to manage their testing and experiment plans. The Slack channel built by his team (ee_experts) brings together CRO experts worldwide to discuss aspects of optimization, share testing wins, and commiserate over failures.

Experiment Engine chose Slack as a way to “get initial traction, foster deeper connections and a sense of unity” with the conversion experts who contribute variants to the Experiment Engine platform. The exclusivity of the platform means that Centenaro can easily limit membership to clients and CRO experts, fostering a tighter and more engaged community through exclusivity.

Community/platform fit

An overlooked aspect of successful communities is something I’ll term “community/platform fit.” Successful community builders know their communities and choose a platform or network that fits best with the psychographics of their target members. Knowing where to build a community can be just as important as the tactics you use to help it grow.

The Startup604 community of technology startup founders and business builders are, by nature, early adopters, who would be likely to engage in a community built on a new platform. This early adoption behaviour was a huge reason El Chami “launched the group at the early stage of Slack knowing that tech people in Vancouver were early adopters and it would get them excited about it.”

Largely due to this strong community/platform fit, Slack has become a popular host for startup, tech, and marketing communities across the globe. An Incomplete List of Communities on Slack (which incidentally does not mention any of the communities cited above) shows that adoption of Slack for networking outside of companies is spreading primarily among professionals likely to exhibit the same behaviours as the Startup604 network. They’re knowledge workers, who tend to constantly test new tools and platforms (and to talk about what works and doesn’t). Building a channel for the right target group using Slack allows communities to thrive.

Community-driven growth

Slack’s explosive growth has been largely organic, relying on word of mouth spreading from user to user and company to company. The rate of organic growth has been truly astonishing, even to the founder Stewart Butterfield, and continues to surpass expectations and projections. The company is a true example of “hockey-stick” growth.

Image via GrowthHackers

Organic channel communities are a powerful user acquisition source for Slack, introducing new users to the platform. Having adopted the platform through a community, users are more likely to bring Slack back to the companies they represent or recommend the tool to their circles. It’s a community-driven rocketship, and a fun one to watch fly.