Substrate Secures $8M in Funding Round to Bring Modern AI Capabilities to All Software Engineers

Substrate Labs, an AI infrastructure startup, has received $8 million in a seed round to deliver elegant APIs that enable developers to build more modular AI systems and accelerate a new era of software development.

The round was led by Lightspeed Venture Partners, with participation from South Park Commons, Craft Ventures, Guillermo Rauch (Vercel), Immad Akhund (Mercury), Will Gaybrick (Stripe), and others. Led by co-founder and CEO Rob Cheung and co-founder Ben Guo, the company also announced the official launch of its API optimized for running ensembles of models.

With Stripe's developer-first strategy in their DNA, the Substrate team is developing a powerful API for AI that harnesses curated open-source AI models across various modalities like text, images, audio, and semantic vectors, and optimizes these models to run at scale—with special emphasis on how quickly one model’s outputs can be used as another’s inputs, according to the company.

Substrate's foundational infrastructure is deeply integrated with SDKs that make it easy to create “graph relations” between models on the Substrate platform, enabling developers to create complex multi-inference AI workflows in several lines of code, with fewer data round trips and maximum parallelism. Early customers include Substack and Maven.

“New AI models offer enormous potential, but the tools developers have access to today are impeding the deployment of intelligence into software systems,” said Rob Cheung, co-founder and CEO. “We built Substrate to help developers create AI-integrated programs intuitively, in the same way they create any other program: by relating small semantic tasks to each other to automate work. The tooling we've created will enable any company—not just tech behemoths—to run dozens of branching ML models in a single request.”

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