Fireworks AI

Fireworks AI provides a fast, production-grade inference platform for running open-source and custom generative AI models, with a particular focus on the raw speed and cost-efficiency of serving large language models at scale. The company built its own inference stack optimized for low latency and high throughput, which matters a lot for consumer-facing AI products where response time directly affects user experience and per-token serving costs directly affect gross margin. Developers can deploy popular open-weight models instantly through a hosted API, fine-tune models on their own data, and deploy custom or fine-tuned checkpoints to dedicated infrastructure when they need guaranteed capacity rather than shared serverless endpoints. Fireworks also supports function calling, JSON mode, and other structured-output features that AI application developers rely on to build reliable agents and tool-using systems rather than free-form chat. Its FireOptimizer and speculative decoding techniques are aimed specifically at squeezing more tokens-per-second out of the same underlying model, which lets startups serve more users on the same budget compared to running unoptimized inference themselves. Fireworks AI is used by AI-native startups building chatbots, coding tools, and voice agents that need enterprise-grade inference reliability without the overhead of managing their own GPU fleet or negotiating directly with a foundation model provider.