Riften
Riften is a YC Summer 2026 (S26) company. Based in San Francisco, CA, USA.
About Riften
Summary
Riften builds an AI infrastructure layer that routes a company's model requests to the lowest-cost capable model, then uses the outcomes of that traffic to fine-tune private, company-owned models on open weights. It targets businesses currently paying frontier labs per token, replacing perpetual API spend with an accumulating intelligence asset the company controls. The stack moves from request routing through automated evaluation to autonomous post-training, all triggered by a single environment variable change.
Business model
Omitted: the sources do not specify how Riften charges customers.
Go-to-market
B2B developer and engineering teams adopt Riften through a low-friction self-serve entry point: a one-line configuration change that redirects existing AI traffic through Riften's gateway, requiring no product rebuild.
From the Y Combinator listing
Earned intelligence for every company
Intelligence will be the most valuable asset a company owns. Today, almost every company rents it. Companies pay a handful of labs one token at a time. Each dollar buys an answer, not an asset. They spend more, but own nothing more. Riften reverses that. Change one environment variable and Riften becomes the gateway for a company's AI traffic. We route each request to the lowest-cost model that can do the job, serving most work on open-weight models we host. Customers save money immediately without rebuilding their products. The gateway is the entry point. Over time, Riften turns the company's work into private models built on open weights and shaped around the business. What begins as cheaper inference becomes an intelligence stack the company owns, runs on infrastructure it controls, and uses to power its most important applications. We call this earned intelligence. It is created by the company's own work, controlled by the company, and accumulated over time. The next generation of companies will not rent their intelligence. They will earn it, own it, and compound it. Riften is how they get there.
Facts
- B2B / B2B -> Infrastructure
- San Francisco, CA, USA
- Active
- Early
Founders (1)
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