Before quitting their jobs, the three co-founders spent roughly a year having informal, unstructured conversations with coworkers and friends at Airbnb, Uber and Coinbase about what frustrated them in existing dev tools, meeting weekly at a bar to compare notes.

After quitting, it took about a month to build a working prototype, which they first put in front of 10 friends rather than the public. One friend's entire 10-person team switched over to Linear after trying it, which gave the founders confidence to widen access.

Rolled out an invite-only private alpha (blog post, tweet, email waitlist) in April 2019. Roughly 10,000 people joined the waitlist; the founders screened signups with a survey and handpicked about 10 new users per week who matched their ICP (IC product builders), running the private beta for close to a year before opening Linear to everyone in June 2020.