The use case: how Cursor deploys Fireworks AI
Cursor uses Fireworks AI as the inference and rollout layer for reinforcement learning of its Composer 2 coding model, running RL across several distributed global clusters without building its own dedicated inference stack.
More reported results
Figures published in Fireworks AI’s case study. They are not independently measured by usedby.
Distributed reinforcement learning across 3–4 global clusters
Cross-region model updates with ~98%+ optimization in transfer size
In the customer’s words
We have finite engineers like everybody else. We would prefer to have engineers make training more efficient and more precise rather than spin up an inference effort....because it's way more performant than the open source engines and is what we use in production. our rl inference scales elastically and globally because of it. when we have low prod traffic we scale up RL, when we have high prod traffic, we scale down RL.Fireworks has been a key partner in helping us train and serve the models behind Cursor at scale. Their platform supports the high-throughput RL workloads and production inference required for Composer, giving us the speed, reliability, and efficiency to keep pushing the frontier of AI coding.We work with Fireworks to push on inference.Other AI tools used by Cursor
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Go straight to the source
Based on Fireworks AI’s published case study. We check the public evidence; the results are reported by the vendor.
fireworks.ai- Source published
- Jun 26, 2026
- Last checked
- Oct 31, 2026
Open source capture What the story claims, and what we checked
What we compared with the page.
- The figure: 6–10xChecked
Printed word for word on the page, near the name of Cursor.
- The passage quoted aboveChecked
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- The numbers in our summaryChecked
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- The publication dateChecked
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- Cursor uses Fireworks AIChecked
Confirmed line.
- The result itselfNot checked
We quote it; we did not measure it.
Fireworks provides the inference and rollout layer that allows Cursor to scale RL without building a dedicated inference system.