The jobs purge sweeping U.S. tech firms has escalated as Amazon said it would shed more than 18,000 workers, and the software maker Salesforce said it would axe 8,000 employees.

Amazon’s reductions are the biggest by a big tech firm over the past year, and the largest set of layoffs in the company’s history, says The Guardian. The online retailer’s chief executive cited “the uncertain economy” for the move and said Amazon had “hired rapidly over the last several years.”

The latest cuts follow a wave of layoffs at tech companies in recent months, including 11,000 jobs at Mark Zuckerberg’s Meta, up to 6,000 at the computer maker HP, 3,750 at Twitter and 1,300 at the company behind Snapchat.

Andrew Jassy, Amazon’s CEO, said in a note to employees January 4 that Amazon had weathered “difficult economies” in the past and would continue to do so. “These changes will help us pursue our long-term opportunities with a stronger cost structure.”

The job cuts represent a swift about-turn for the retailer that recently doubled its basic pay ceiling to compete more aggressively for talent.

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The layoffs amount to 6% of Amazon’s roughly 300,000-person corporate workforce, and equate to about 1.2% of the company’s global workforce of more than 1.5m. Salesforce, meanwhile, said it was laying off about 8,000 employees, or 10% of its workforce.

Marc Benioff, now the sole chief executive at Salesforce, told employees in a letter that he blamed himself for the layoffs after continuing to hire aggressively in the pandemic.