E2B: Secure Cloud Sandboxes for AI Agent Code Execution
E2B is the essential infrastructure for AI agents that execute code. Providing secure, isolated cloud sandboxes powered by Firecracker microVMs, E2B enables autonomous agents to run untrusted code, access file systems, install packages, and accomplish complex tasks all without risking production infrastructure or user data.
Founded with $21M in funding (July 2025), E2B is positioning itself as the universal sandbox standard for the AI agent era. Adopted by Manus, Perplexity, Hugging Face, and 50+ Fortune 500 companies, E2B has become the infrastructure that makes agentic AI actually work at scale.
The Code Execution Problem
AI agents need to execute code to deliver value: data analysis, software development, research, system automation. But executing untrusted code code written by an LLM that hasn't been reviewed is dangerous.
Traditional Solutions Have Critical Weaknesses:
- Local Execution:Ties up your infrastructure. What if a loop runs forever? What if code deletes files?
- Docker Containers:Faster than full VMs but insecure. Shares the host kernel, making container escape possible. Not designed for untrusted code.
- Full Virtual Machines:Secure but slow. Takes 10-20 seconds to start unacceptable for agents that need to run hundreds of times per interaction.
- Disable Code Execution:Limiting agents to reasoning-only severely constrains their capabilities.
E2B solves this with Firecracker microVMs.
E2B Architecture: Firecracker-Powered Security
Firecracker is open-source virtualization technology from AWS, originally built for AWS Lambda. It provides hardware-virtualized, kernel-level isolationmeaning each sandbox has its own operating system kernel, completely isolated from the host and from other sandboxes.
Result: Agents can execute code safely. One sandbox's code cannot access another's data, cannot access the host system, cannot escape to exploit the kernel.
E2B Capabilities
Code Execution Environments
Execute Python, JavaScript, Bash, and other languages. Capture output, parse results, iterate until code works. Cell-based execution (Jupyter-like) for interactive development.
File System Access
Agents can read/write files, create directories, manage permissions. Upload data to sandbox, download results. Perfect for data analysis and file-based workflows.
Session Persistence
Free tier: up to 1-hour sessions. Pro tier: up to 24-hour sessions. Agents maintain context across multiple executions, enabling complex multi-step workflows.
Scalability
Sandboxes spin up in ~150ms and consume ~45MB memory. Spin up 100 sandboxes concurrently with no resource conflict. Perfect for handling parallel agent execution.
Resource Isolation
Define CPU, RAM, disk limits per sandbox. Prevent runaway code from consuming infinite resources. Network restrictions (optional whitelist-only outbound traffic).
MCP Tool Integration (Nov 2025)
Partnership with Docker provides access to 200+ MCP tools from Docker Catalog. Agents can call GitHub, Stripe, Notion, and other tools directly from sandboxes.
Multi-Tenant Security
Each session gets isolated kernel, filesystem, processes. User A's data completely isolated from User B's sandbox. Metadata separation prevents side-channel attacks.
Long-Running Agents (New in 2025)
Manus agents now run for extended periods hours to days. Pause for user confirmation, gather context over time, deliver complex artifacts. E2B sessions maintain state across entire workflows.
Real-World Impact: What Becomes Possible
Autonomous Data Analysis
User uploads dataset. Agent writes Python code to analyze it. E2B executes code safely. Results returned to user in seconds. No local Python environment needed, no data security concerns.
AI-Generated Software
Agents write entire applications (Next.js frontends, backend APIs, databases). E2B executes code, tests it, iterates. Delivers working, tested code to developers.
Long-Running Research Agents
Agents conduct extended research: search multiple sources, gather data, analyze findings, write reports. Sessions maintained for hours while agents gather context and produce comprehensive outputs.
Secure SaaS Code Execution
Users upload or generate code. Platform executes in isolated sandbox. Code cannot access platform internals, user data, other users' data. Results safely displayed to user.
Enterprise Automation
Agents execute scripts, manage infrastructure, process data pipelines. All safely isolated from production systems.
Manus Example
AI agents accomplish complex real-world tasks end-to-end using full OS access terminal, file system, browser, applications. Same environment humans use. Agents can install packages, run commands, manage files.
Security First
E2B's entire design centers on security:
Kernel-Level Isolation
Separate Linux kernel per sandbox provides hardware-virtualized isolation. One of the most secure solutions available for running untrusted code.
Process & Resource Limits
CPU, memory, disk, network, and process count limits prevent resource exhaustion attacks. Timeouts prevent infinite loops.
Network Security
Optional network restrictions enforce whitelist-only outbound traffic. Prevent data exfiltration.
Audit Trails
Every execution logged. Compliance-ready for regulated industries (finance, healthcare, government).
No Shared State
Completely isolated filesystem, memory, processes per sandbox. Zero cross-contamination between users/sessions.
Pricing & Accessibility
Hobby Tier (Free)
- • $100 one-time usage credits
- • Up to 1-hour sandbox sessions
- • Up to 20 concurrent sandboxes
- • Perfect for: Experimentation, demos, proofs-of-concept
Pro Tier ($150/month)
- • Includes subscription + usage-based billing (~$0.000014/vCPU-second)
- • Up to 24-hour sandbox sessions
- • Up to 100 concurrent sandboxes
- • Customize CPU & RAM per sandbox
- • Perfect for: Production agents, long-running workflows
Enterprise (Custom)
- • Custom pricing & Dedicated support
- • BYOC (Bring Your Own Cloud) options
- • Custom compliance and SLAs
- • Perfect for: Large enterprises, Fortune 500 companies
Enterprise Adoption
Fortune 500 & Leading AI Companies
Manus (general-purpose AI agents), Perplexity (code analysis), Hugging Face (model evaluation), Mistral, OpenAI (early support), and 50+ unnamed Fortune 500 companies.
Industry Recognition
Insight Partners (Series B lead): "E2B is pioneering essential infrastructure for AI agents."
Prediction: "E2B's sandbox standard will become a cornerstone of secure and scalable AI adoption across the Fortune 100."
Open-Source & Community
E2B is committed to open-source governance with SDKs in Python and JavaScript/TypeScript, community contributions, transparent roadmap, and integration with Docker MCP Catalog and broader ecosystem.
Why GenAI Protos Builds on E2B
At GenAI Protos, code execution is fundamental to agent capabilities. E2B is essential because:
- 1. Safety & TrustClients trust that agent code runs safely, isolated from their infrastructure. E2B's Firecracker isolation is the most secure available.
- 2. Speed & Performance150ms sandbox startup enables sub-second agent execution. No cold-start delays, no resource contention.
- 3. ScalabilitySpin up thousands of sandboxes in parallel. Agents can execute code concurrently without infrastructure overhead.
- 4. Long-Running WorkflowsPro tier supports 24-hour sessions. Agents can conduct extended reasoning, maintain context, produce complex artifacts.
- 5. Cost EfficiencyPay only for compute used. ~$0.10 per 1-hour 2vCPU sandbox. Scale to enterprises without runaway costs.
- 6. Fortune 500 PedigreeAdopted by major enterprises and AI leaders. Proven in production at scale.
"For enterprises deploying autonomous agents, E2B provides the infrastructure that transforms agents from theoretical to practical agents that execute code safely, at scale, cost-effectively."
Need a secure code execution layer for your agents?
Let’s design an E2B-backed architecture so your AI agents can execute code safely at scale.
E2B Secure Sandboxes FAQ
Answers to common questions about E2B sandboxes, Firecracker isolation, supported workloads, and how GenAI Protos uses E2B for code-executing agents.