Agentic cloud infrastructure startup E2B said today it has raised $21 million in early-stage funding to build out an entirely new, open-source infrastructure for running artificial intelligence agents securely in the cloud.

The startup, officially known as FoundryLabs Inc., said today’s Series A round was led by Insight Partners and saw participation from Decibel, Sunflower Capital, Kaya and well-known angel investors such as former Docker Inc. Chief Executive Scott Johnston.

E2B’s vision is to provide businesses with a dedicated, open-source cloud infrastructure stack for AI agents. It believes that the best place for AI agents to be hosted is in secure sandboxed environments in the cloud, where it will provide them with safe computer and browser-use features to automate various complex business tasks.

Co-founder and Chief Executive Vasek Mlejnsky (pictured, right, alongside co-founder and Chief Technology Officer Tomas Valenta) said he hit upon the idea for a dedicated, sandboxed cloud environment for AI agents after building his own agentic system. While doing that, he came to realize that existing cloud infrastructure has been designed specifically for humans rather than AI agents, and that it’s not possible for them to use it efficiently.

“How can we expect AI agents to do the same work as humans if we can’t give them the same environment to use the tools we use?” he asked.

Mlejnsky explained that enterprises have massive expectations for AI agents due to all the hype around them, but he believes that they won’t easily scale if they’re built on legacy infrastructure that’s not designed to be used by them. “E2B solves this by equipping AI agents with safe, scalable and highly-performant cloud infrastructure, as well as tools that help agents to scale in production,” he added.

With E2B’s sandboxed cloud environments, AI agents get access to the same computational capabilities as human workers do, meaning their own computer plus a browser and other tools that enable them to retrieve information, as well as a file system to store that data, and compute platforms for executing AI-generated code.

Companies can quickly spin up and shut down these sandboxed cloud environments as needed, and they can scale rapidly to millions of virtual personal computers, allowing enterprises to unleash armies of agents that can work even more efficiently than humans do. It’s all hosted in a simple and secure runtime that enables reinforcement loops for AI training and agentic workflows to run rapidly.

“All of the main use cases we see for AI agents need not only high scale but also extremely high speed,” Mlejnsky said. “Agents building a full website and making research reports need to give you an answer in a lower seconds. There’s no other way to do this today, especially securely and no open-source alternative than us that customers can deploy inside their clouds.”

Holger Mueller of Constellation Research Inc. said E2B is making a good case, from both an architectural and a usability perspective, that agentic AI systems need their very own, specialized infrastructures. “The key will be how well E2B is able to use the funding to materialize this new architecture it’s promising,” the analyst added. “Enterprises will be watching, because we are moving toward an agentic future that’s likely to come much sooner than later.”

E2B says its vision has been embraced by dozens of Fortune 500 companies, as well as AI industry leaders such as Hugging Face Inc., Perplexity AI Inc. and Manus. With the money from today’s round, E2B aims to position its open-source sandbox protocol as the universal standard for AI agents, and has plans to add additional functionality such as “secrets vaults” and orchestration tools for managing fleets of AI agents from a single console.

Praveen Akkiraju of Insight Partners said he believes E2B is pioneering “essential infrastructure” for AI agents and predicts its sandboxed cloud environments will become widely used in the near future: “We believe that E2B’s open-source sandbox standard will become a cornerstone of secure and scalable AI adoption across the Fortune 100 and beyond.”

Photo: E2B