Facebook owner Meta has started notifying staff who are losing jobs in the wave of 10,000 job cuts the social media company announced last month, reports BBC.
Boss Mark Zuckerberg had said the layoffs are key to making the company more efficient.
Meta, which also owns Instagram and WhatsApp, has been under pressure since a sharp slowdown in its ads business last year.
It had already let go 13% of its staff - roughly 11,000 people - last year.
Some of the people affected by Meta's latest decisions wrote on social media saying they were looking for new roles.
The company declined to comment, pointing to the March memo in which Mr Zuckerberg outlined the plans, describing last year's challenges as a a "humbling wake-up call".
He said the cuts were necessary to adjust to a new "economic reality" and enable the firm to invest in the future.
In March, people on the recruitment team were first to leave the company.
The newest notifications apply to people working on the firm's IT teams, according to the firm's plans.
Another round of layoffs affecting business and administration teams is expected next month.
The firm has said timing could differ for people outside of the US and some cuts may not be complete until the end of the year.
The moves come as the corporate world is bracing for a wider economic slowdown, as higher borrowing costs start to slow business activity.
The tech industry, where low borrowing costs had helped fuel investments and growth, has been hit particularly hard.
More than 170,000 people in the industry have been laid off globally since the start of the year, according to announcements tracked by website layoffs.fyi, with big names such as Amazon and Google accounting for some of the largest actions.
Among the other announcements this week, online property firm Opendoor said it would reduce its workforce by roughly 560 jobs or 22%.