He also tweeted, cryptically, about “manual delivery” of tweets by Demi Moore and Ashton Kutcher, two early Twitter power users who joined the site in 2009, when they were a married couple. (Kutcher’s presence on Twitter briefly became fraught the same year, when reports suggested that the site wasn’t letting users unfollow the That '70s Show while he was bearing down to win a contest to become the first user with a million followers.)

Weaver, who worked in a variety of roles for the social giant between 2008 and 2011, wrote that “intersections between two popular users would time out.” When Lady Gaga tweeted, he said, the site ignored tweets by other users for an entire 20 seconds.

Evan Weaver, a former technical lead and architect at Twitter, reminisced last night about the site’s early infrastructure woes. One startling claim: when the site was first blowing up, its system was stretched so thin that it couldn’t handle two popular users tweeting at the same time.

Reached by phone, Weaver clarified that in the early days of Twitter, the system choked when one user with a high follower count replied to another — a common problem with Moore and Kutcher. When Twitter co-founder Evan Williams went on the Oprah show to talk about Twitter, Weaver anticipated a huge influx of new users, and implemented a workaround specifically to handle interactions between Moore and Kutcher.

“We had to manually run a script on a laptop that would specifically check if they had tweeted to each other so that they would see it in real time,” he said. “Hell or high water, we had to make sure that nothing would go wrong.”

The company’s early concern with micromanaging celebrity accounts is intriguing in light of the company’s current struggles to define rules around controversial content and misinformation originating from popular accounts.

Jason Goldman, who served as Vice President of Product at Twitter between 2007 and 2010, responded to Weaver’s tweets with the observation that early Twitter was “held together by sheer force of will.”

Weaver shared other war stories about Twitter’s early days. In one incident, he wrote, an error caused every user to log in as somebody else each time they refreshed the page.

Jon Christian is a contributing writer for The Outline.