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Riften
YC S26San Francisco, US · Founded 2026 · 5 employees · 2 known investors
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Riften provides a routing layer that sits between a company's applications and large language model APIs, directing each request to the least expensive capable model and using self-hosted open-weight models where possible to reduce inference costs. It also uses the resulting task data to train private, company-owned models on recurring work, serving businesses that run AI-powered applications.
AI & Machine LearningData & InfrastructureDeveloper ToolsEnterprise SoftwareReinforcement LearningInfrastructureAIUnited States of AmericaAmerica / Canada
Founders & leadership· Y Combinator alumni (S26)
Riften was founded in 2026 by Carl Stauffer.
CS
Carl StaufferFounderCarl Stauffer is the founder and CEO of Riften, which routes requests between applications and language model APIs to lower inference costs. He previously worked as a Forward Deployed Engineer at Palantir and as a nuclear researcher at Jefferson Lab, and studied computer science and applied mathematics at Johns Hopkins.
Investors · 2
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corporate structureRiften Inc.
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Frequently asked questions
- What does Riften do?
- Riften provides a routing layer that sits between a company's applications and large language model APIs, directing each request to the least expensive capable model and using self-hosted open-weight models where possible to reduce inference costs. It also uses the resulting task data to train private, company-owned models on recurring work, serving businesses that run AI-powered applications.
- Who founded Riften?
- Riften was founded by Carl Stauffer in 2026.
- Who are Riften's investors?
- Riften's investors include Vela Partners, Y Combinator.
- Where is Riften headquartered?
- Riften is headquartered in San Francisco, US.