Elon Musk gave Twitter employees an ultimatum in a midnight email: commit to a “hardcore” culture at Twitter or leave with severance. The Washington Post reports that Musk has asked Twitter employees to sign an online form by 5PM ET today committing to “long hours at high intensity.” If Twitter employees refuse to sign the form then they will reportedly receive three months of severance pay.

Former Uber engineer Gergely Orosz, who has been reporting on Twitter’s internal changes this week, says Musk’s email outlines a “Twitter 2.0” that will be driven by engineers with “those writing great code” taking a more important role inside the company.

The email arrived barely a week after Musk’s first meeting with Twitter employees, and two weeks after he ordered mass layoffs — cutting roughly half of Twitter’s global workforce. “What works at SpaceX and Tesla is people being in the office and being hardcore,” said Musk during his first meeting with Twitter employees following the cuts.

That language was mirrored in the email to Twitter employees today, with Musk demanding that employees “will need to be extremely hardcore.” Musk has previously asked Tesla workers to “go super hardcore” to meet targets.

Musk previously pushed Twitter employees to launch a new version of Twitter Blue with paid blue check verification with a deadline that would result in firings if it wasn’t met. The new Twitter Blue, which now costs $7.99 per month and gets you a blue verified check mark, eventually launched and quickly led to impersonation and chaos on the social network.

Update, 5:15AM ET: Article updated with more email details from Gergely Orosz.