Atreides Management, Index Ventures and TCV led the Series D round, which values the San Mateo, Calif.-based firm at US$17.5 billion. Teachers’ Venture Growth unit made the pension plan’s investment. (The Logic)

Talking point: Major tech firms like Shopify and Uber, and AI application developers like Cursor and Vercel, use Fireworks’ software and infrastructure to fine-tune and run open source AI models. The startup’s technology lets clients take advantage of those cheaper systems without the expense and hassle of hosting them in-house. Most of the leading models Fireworks offers are from Chinese developers like Alibaba, DeepSeek, Moonshot AI and Z.ai, but the firm operates them out of data centres in the U.S., Germany, Iceland and Japan to address security concerns. Fireworks said it’s now bringing in revenue that would surpass US$1 billion on an annualized basis. Competitors Baseten and Together AI have also recently raised mega-rounds, amid booming demand for tools that can help companies cut the costs of their AI applications while maintaining more control over their data.