Fireworks AI runs a platform where developers can access, customize, and deploy open-source AI models through a fast and affordable cloud service. They have deeply optimized how models run on graphics processors, squeezing significantly more speed out of each chip than standard approaches.

Fireworks differentiates through its compound AI system approach, allowing developers to compose multiple models and tools together in a single API call, and through deep kernel-level optimizations that squeeze more performance from each GPU. Their FireAttention engine and custom CUDA kernels deliver significantly faster token generation than standard serving frameworks.

The rapid proliferation of open-source AI models and enterprise adoption of LLMs has created a massive market for optimized inference platforms, driving Fireworks' growth as developers seek faster, cheaper alternatives to self-hosting. Fireworks AI raised $250M at a $4B valuation in October 2025 in a Series C led by Lightspeed Venture Partners, Index Ventures and Evantic.