PART 1 - TONS OF PUNKS, ONE BIG JERK CHAPTER 4: KEYSTROKES AND BRUSHSTROKES A Pint Is All You Need

"Slack was based on an internal communications system Stewart Butterfield’s team created while building the failed game Glitch."

WIRED's 2014 profile directly connects Slack to Tiny Speck's internal Glitch-era communications system and the game's failure.

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