‘No longer fly-by-night’: Slack founder sends message to email users

Operating as a one-man tech support is one of the perils of the job for Slack co-founder  and chief technology officer Cal Henderson.

Meeting Henderson for coffee on his most recent visit to Melbourne, I can’t help but suggest a few tweaks to the workplace messaging service like prohibiting double messaging via both email and Slack.

Cal Henderson is the co-founder of Slack which has 85,000 paid customers globally.
Cal Henderson is the co-founder of Slack which has 85,000 paid customers globally. Credit:Jason South

After all, Slack is supposed to be an alternative to communicating primarily through email with Henderson describing the service as “at its core, a messaging platform for teams”.

“We have been using email in the workplace for 30 or 40 years and a lot of what we think about how we communicate is dictated by the shape of the tools,” he says.


“It’s not like email was designed to be used in the way and at the scale of how we use it at the moment. It is really a digitisation of the office memo. There is a lot of formality and structure behind it for a tool that you use to communicate with people … every day.”

Henderson points to the requirement for a subject line, salutation and sign off in emails as “a lot of infrastructure” for a product that is used frequently.

We are no longer a fly-by-night startup that might disappear tomorrow, we are a serious going concern.

Cal Henderson, Slack co-founder

“More systemic is that [email] is explicitly by default one to one, you choose who uses each piece of communication,” he says.

In contrast, Slack uses “channel-based messaging” where information is shared.

Rapid growth

Slack was started in 2009 from the detritus of a failed video game company, Glitch, which Henderson ran with Eric Costello, Serguei Mourachov and Stewart Butterfield.

However, the founders realised the ad hoc tools they had been using to communicate while running Glitch “could maybe work for other small engineering teams like ours”.

Slack has grown rapidly in the 10 years since its launch and while the company won’t provide user numbers in Australia, the platform has 85,000 paid customers globally and works with “thousands of teams” in Australia including Xero and Seek.

Last year, it reported revenues of $US400 million ($581 million) but it is still not profitable, posting more than $US138 million in losses.

The platform listed on the New York Stock Exchange in June and Henderson says going public has added legitimacy to the company.

Slack hacks from Cal Henderson

  1. My biggest tip is definitely what we call the quick switcher. Apple K or Control K allows you to switch between channels really quickly. 
  2. Starring channels. You can choose particular channels which are most important to you and have them pop to the top of your list. I star all of my most important channels I know I want to read every day.
  3. Setting do not disturb hours. This is for the times at which if somebody sends you a message you don’t need to know about it. Outside of work hours I don’t need to be contacted unless it is an absolute emergency. 
  4. Emojis aren’t just for personal use, they have business benefits too. Emojis add tone and sentiment to written communication as well as passing on feedback quicker. For example, reacting with a green tick is more efficient than typing out separate lines of approval.

“In talking to large companies it is definitely more confidence-inspiring. We are no longer a fly-by-night startup that might disappear tomorrow, we are a serious going concern,” he says.

Over the past year, shares have fallen from $US40 to as low as $US19 but Henderson says he is focused on long-term value and growth.

“We are happy with the fundamentals of the business,” he says. “One of the downsides of being a public company is we are more subject to the whims of the market rather than the realities of the business.”

Cal Henderson says Slack will never be an email killer.
Cal Henderson says Slack will never be an email killer. Credit:Jason South

Herding people

Henderson says Slack has succeeded because it helps align people within a team and a broader business.

“Herding people is way more difficult than machines it turns out,” he says.

He acknowledges one difficulty users can encounter with Slack is when people continue to email as well as communicate via Slack, doubling the amount of communication rather than cutting back on email.

“That is not a mistake people are making, rather we are not providing enough guidance as to how Slack can be best used,” he says.

Henderson acknowledges for people outside an organisation or for talking to someone for the first time “email is a great tool”.

“Slack, as the product is now, is never going to completely kill email,” he says.

Most Viewed in Business

Source: Thanks smh.com