User onboarding guru Samuel Hulick wrote a February 2016 Medium post about how he was "breaking up" with this company's product because it was asking for "A LOT" of his time.  
In an interview with MIT Technology Review, the CEO of this company called its product "just a giant piece of shit. Like, it's just terrible and we should be humiliated that we offer this to the public."  User onboarding guru Samuel Hulick wrote a February 2016 Medium post about how he was "breaking up" with this company's product because it was asking for "A LOT" of his time.  Mattermost is an open-source rival to this company's product.  Ben Thompson has forecasted that this company's Botkit framework will make it the winner of a post-Facebook internet age.  The CEO of this company had earlier co-founded Flickr and is named Stewart Butterfield.  This company grew out of a failed startup called (*) Tiny Speck, which developed a side-scrolling MMO called Glitch.  Similar to IRC, people using this company's service communicate through open channels.  For 10 points, name this company which makes a popular enterprise chat app.
In an interview with MIT Technology Review, the CEO of this company called its product "just a giant piece of shit.
Slack