E2B
E2B is an AI Agent Infrastructure company founded in 2023 and based in San Francisco, United States. It has raised $35M in total funding, most recently a Series A in 2025.
Open-source secure cloud sandboxes that give every AI agent its own isolated Linux computer to run code, browse files, and use real-world tools — adopted by 88% of the Fortune 100. Founded in 2023 in Prague by Vasek Mlejnsky and Tomas Valenta, E2B spins up firecracker-based microVM sandboxes in under 200 milliseconds, allowing AI applications from Hugging Face, Perplexity, and enterprise agent platforms to safely execute LLM-generated code at massive scale. The company has raised about $35M total, including a $21M Series A led by Insight Partners in July 2025, on the back of running millions of sandboxes per month with strong growth.
Every serious agent product needs a sandbox runtime, and E2B has become the de facto open-source standard — the Stripe-style developer-first primitive for the agentic computing era.
e2b.dev ↗·AI Agent Infrastructure·
United States·private 
