Rising AI cloud provider and IPO candidate CoreWeave revealed fast-growing revenue from a “limited number of customers,” including Microsoft, and how it has scaled its GPU-powered data centers to compete with the Amazon Web Services and other rivals in its S-1 filing on Monday.

CoreWeave, a cloud-computing provider that’s one of the hottest startups in artificial intelligence, filed for an initial public offering disclosing rapidly growing revenue.

Data center operator Switch is weighing an IPO at about a $40 billion valuation, Reuters reported in September. Nvidia rival Cerebras Systems mulled going public last year but postponed its roadshow amid delays with a U.S. national security review, Reuters has reported.