When Slack was founded, the company designed a tool to make work easier for a team of engineers building together. Six years and an IPO later, the company has burst into the world's largest enterprises, with its platform used by every type of business imaginable from banks, large tech firms, and startups boasting anywhere from 10 to 200,000 staff, and beyond.
The founders behind Slack thought they had found a nice little niche, but what they soon realised was the software-as-a-service (SaaS) explosion, and the proliferation of consumer applications such as Facebook and WhatsApp in the enterprise, would open up far more ground to cover.
Work is also happening in a more fragmented way, and as Slack CTO and co-founder Cal Henderson told ZDNet, there's not previously been one place that it can all come together.
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Prior to Slack, applications promising productivity focused on how to automate more of an individual's work, rather than how a team could boost productivity by having quick access to other elements of, and people from, the business.
"As automation has removed more and more repetitive tasks, the remaining work, the remaining kind of human-differentiated work, is much more collaborative. More and more knowledge workers are coming, even roles that have been thought of as traditionally solo, like journalism, are more and more collaborative," Henderson said.
"And so while all of this kind of proliferation and advancement of software, very focused on individual productivity, how do you take the task that somebody does by themselves and make it faster, more accurate, higher quality of output -- individual productivity has been well-served by software transformation -- but there hasn't been the equivalent in thinking about this new productivity, how do you take a team of people and make them more productive together?"
Slack's main competitor, Henderson said, is the status quo -- organisations that say they're using email, despite that often being a combination of email, text message, WhatsApp, Facebook Messenger, phone calls, and Skype.
Speaking with ZDNet while in Australia last week, Henderson discussed another shift in how people are finding balance between work life and home life.
"The social aspect of work, I think that has become one of the changes which isn't unique to technology," he said. "What's happening as well is that by maybe the end of this year, beginning of next year, around half of all employees or knowledge workers will be millennials."
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With that, he explained, people are also bringing a different set of expectations to their relationship with work, covering the software tools they use and also how they work.
"People want to feel closer to the work that they're doing, they want to understand the mission of your company, they want to understand how the work that they do ties to that mission," he said, noting also the shift in where work stops and fun starts.
"Employee tenure is generally going down and people don't expect to work at the same place for life ... there is much more competition for talent and the employee experience, as a whole, is seen as much more important."
While Slack was initially pitched as a way for those working together to ditch email -- email after all is a terrible tool for talking to the person who sits across from you -- Henderson said it won't be the death of email, but it can certainly continue to make it more irrelevant.
"There's all that formality and structure around it and if you send an email; you have to fill out the subject line, ask how somebody's family is before you get to the point and the bit of information that you want, a little nugget in the middle, and a sign off, the name, and the 'don't print this, save the trees' -- all of that structure fits around the thing that you're trying to do for somebody that you talk to hundreds of times a day. It's not a tool that's designed for that," Henderson added.
"Reply email chains, which may never die for years -- email just wasn't designed for that purpose. It wasn't built for teams of people to work together, it was built for taking the entire office memo and digitising it ... and it's now just being used for every kind of team communication, which doesn't make sense."
It also isn't a tool that allows for new team members to get a whole picture of what they're joining, and when a team member leaves, their email also leaves.
"Your inbox is a place other people's information goes to die," he said.
Slack is used by every organisation differently, but use of the platform continues to grow alongside the various ways businesses make it work for them.
Slack allows for all team communication to be centralised; conversations can be segmented by channels and management can have visibility over this if they wish.
Channels can also be searched for content.
It integrates with so many enterprise applications, such as Jira, Box, and GitHub; and as users can access Slack on desktop and mobile, they can respond to messages on the go. Much the same way individuals use consumer apps such as WhatsApp and Facebook Messenger.
Slack recently underwent a large-scale transformation, with the major performance update to its desktop and web client seeing the company re-write the entire code for its desktop client -- its oldest piece of codebase -- from scratch.
"When we first started building Slack six and a half years ago, we didn't really have any vision of how many people would use it, how many hours a day they would have it open, or how many different Slack instances they would be in," Henderson said.
"We built it first, assuming you would only ever be in one ... and as we started to see more and more usage -- that terrible story that people who use Slack the most have the worst possible experience."
Six and a half years is also a very long time in the world of web tech.
"Web technology changes fairly fast and all of the state-of-the-art from six and a half years ago was now dinosaur age, so at least we're now within a year of being modern. Unfortunately, that'll be part of the treadmill forever," he said.