Best E2B alternatives for secure code execution in 2026

AI developers use sandbox platforms to execute AI-generated code, user-submitted scripts, and agent tasks without granting them unrestricted access to production systems. These environments may be disposable or persistent, depending on what the agent needs between tasks.

E2B provides Firecracker sandboxes and SDKs for this purpose. Alternatives are worth comparing when you need a different session model, GPU support, deployment location, or billing structure.

This article covers:

• What E2B Sandbox is and how it works
• Why secure sandboxing matters for agent workflows
• Which E2B limits to consider
• How Northflank, Daytona, Vercel Sandbox, and Modal compare on isolation, persistence, deployment, and pricing

LLMs frequently generate code as part of coding agents, developer copilots, and internal tools. That code may read sensitive files, make network requests, modify state, or consume more resources than intended.

Sandboxing reduces exposure by:

• Separating execution through a runtime such as a microVM or gVisor
• Restricting network access and credentials
• Applying resource limits and execution timeouts
• Keeping different users' files and execution environments separate

Isolation is one part of the design. The application must still decide which data a task can access and what state survives afterward.

• Users upload or generate scripts
• AI agents invoke tools, install dependencies, or write files
• Your product runs many users' code concurrently

E2B provides Firecracker sandboxes for AI-generated code, with Python and TypeScript SDKs. Developers can create environments, run commands, work with files, and manage sandbox lifecycles programmatically.

• Isolation: Firecracker microVMs provide a separate guest kernel for each sandbox.
• Agent integration: SDKs simplify code execution and filesystem operations.
• Persistence: Pause/resume preserves state between tasks. Normal pause retains memory and files; filesystem-only pause retains files and reboots on resume.
• Deployment options: Enterprise bring your own cloud (BYOC) supports AWS, GCP, and Azure, with E2B operating the cluster.

• Session limits: Hobby allows up to one hour per session and Pro up to 24 hours. Enterprise offers custom limits.
• Concurrency costs: Pro includes 100 concurrent sandboxes; higher concurrency costs extra.
• GPU workloads: E2B does not provide GPU compute in its standard sandbox offering.
• Customer-cloud access: Bring your own cloud (BYOC) requires an Enterprise agreement.

These are reasons to compare platforms against your workload, rather than treating E2B as limited to demos or experimentation. Its enterprise overview describes deployment and scaling options.

• Hobby: No subscription fee, with a $100 one-time usage credit and 20 concurrent sandboxes.
• Pro: From $150/month plus usage, with 100 concurrent sandboxes and sessions up to 24 hours.
• Enterprise: Custom pricing, limits, and deployment terms.

Standard compute rates are $0.0504/vCPU-hour and $0.0162/GiB-hour. Pausing and resuming an environment is different from keeping it continuously running; a session limit does not mean E2B has no persistence.

E2B and its alternatives are typically used to:

1. Execute LLM-generated code through tool-calling workflows.
2. Run coding agents and internal developer assistants.
3. Create isolated environments for testing and debugging.
4. Run data analysis or generate visualisations and return the results to an application.
5. Host MCP servers or other tools an agent needs, subject to the platform's networking and runtime limits.

If end users or agents execute code on shared infrastructure, scope their access and isolate their environments.

Northflank provides secure, isolated sandbox environments for AI agents and untrusted code execution. Run coding agents, scripts, generated APIs, repository builds, and GPU tasks in custom environments, with support for thousands of concurrent sessions and no fixed session time limit.

Northflank Cloud offers sub-second sandbox boot times, with microVM isolation for CPU sandboxes and gVisor for GPU sandboxes. Attach persistent volumes when files need to survive restarts or pauses, and manage creation, execution, and cleanup programmatically.

With bring your own cloud (BYOC), Northflank acts as the control plane to run coding agents and their sandboxes in your virtual private cloud (VPC). Workload execution stays in your environment; standard deployments use Northflank-hosted orchestration metadata.

Strengths:

• Fast, concurrent execution: Run separate environments for agents, users, or tasks and scale capacity around their resource needs.
• Custom environments: Use container images with your preferred languages, dependencies, and agent tools.
• Flexible sessions: Run short-lived tasks or keep sandboxes active without a fixed session cutoff.
• Persistent files: Attached volumes preserve files across restarts and pauses.
• CPU and GPU execution: Run ordinary code execution and GPU tasks in sandbox environments.
• Private deployment: Self-serve bring your own cloud (BYOC) supports multiple cloud providers and private infrastructure options.
• Programmatic control: Manage workloads through APIs, SDK clients, CLI tooling, and reusable deployment configurations.

Limitations:

• Customer-cloud setup: Sandbox isolation requires a supported runtime class and compatible infrastructure.
• Pause behaviour: Pausing stops processes; attached volumes preserve files, not running memory state.

Who it's for:

• Teams running AI agent sandboxes and multi-tenant code execution at scale
• Teams that need long-running sessions, custom environments, or GPU tasks
• Companies that need sandbox execution in their own infrastructure

Pricing: $0.01667/vCPU-hour and $0.00833/GB-hour, with H100 GPU plans at $2.74/hour all-inclusive (CPU and RAM included). The free developer Sandbox tier offers always-on compute with no sleeping, two free services, one database, and two cron jobs. Pay-as-you-go supports CPU and GPU workloads with per-second billing. Enterprise plans add custom terms, 24/7 support, SLAs, and enterprise access controls. See the full pricing details for additional GPU options and plans.

Runtime limits and pricing checked October 2, 2026. Startup figures are not a like-for-like benchmark: compare the time to a usable environment with your own images and workload.

Daytona provides programmable environments for agents, including container, Linux VM, Windows, and GPU sandbox classes. It supports persistent files and interactive command execution.

Strengths:

• Environment configuration: Build environments from images and reuse snapshots.
• Persistence: Retain files between tasks; VM sandboxes can preserve memory through pause/resume.
• Interactive execution: Stream session output and run commands programmatically.
• Customer-managed compute: Attach your own runner infrastructure through custom regions.

Limitations:

• Lifecycle differences: Persistence and pause behaviour vary by sandbox class; GPU sandboxes are ephemeral.
• Infrastructure responsibility: Customer-managed compute requires your team to operate the underlying machines and capacity.

Who it's for:

• Teams building coding agents with configurable environments
• Teams that want snapshots, interactive execution, or customer-managed runner capacity

Pricing: Usage-based, with $200 in free credits. Standard CPU costs $0.0504/vCPU-hour and memory $0.0162/GiB-hour; storage and GPU usage have their own rates.

Vercel Sandbox provides Firecracker environments for untrusted code execution through SDKs and a CLI. It supports streamed command output and filesystem snapshots for reusable environments.

Strengths:

• MicroVM isolation: Firecracker separates sandbox execution from the host.
• Developer access: JavaScript and Python SDKs plus CLI commands for sandbox lifecycle and execution.
• Persistence options: Snapshots preserve filesystem state; Drives provide shared persistent storage in public beta.

Limitations:

• Session duration: Up to 45 minutes on Hobby and 24 hours on Pro and Enterprise.
• Deployment model: Runs on Vercel-managed infrastructure, rather than in your own cloud account.

Who it's for:

• Teams using Vercel that need agent code execution
• Applications that can fit execution within the applicable session limits

Pricing: Hobby includes usage quotas. Paid plans meter sandbox usage, including active CPU and provisioned memory. In the default region, rates are $0.128/active-CPU-hour and $0.0212/GB-hour of memory; storage and other usage are also metered.

Modal provides programmatic sandboxes for code execution and GPU workloads. It supports custom images, persistent Volumes, and snapshots, rather than being limited to stateless function execution.

Strengths:

• Custom environments: Build images programmatically or use existing container images.
• GPU execution: Run sandbox workloads on managed GPU infrastructure.
• Persistence: Use Volumes and filesystem snapshots to retain work between environments.
• Network controls: Restrict outbound access according to the destinations your task needs.

Limitations:

• Session duration: A sandbox can run for up to 24 hours; longer workflows need to preserve and restore state.
• Deployment model: Bring your own cloud (BYOC) is not available.
• Runtime differences: The VM runtime is CPU-only and in beta; memory snapshots have retention and compatibility limits.

Who it's for:

• Teams running GPU-intensive AI agent tasks
• Developers who want code-defined compute environments and managed scaling

Pricing: Sandbox CPU costs $0.1419/physical-core-hour, equivalent to two vCPUs, and memory costs $0.0240/GiB-hour. Starter includes $30/month in compute credits. Team costs $250/month plus compute, with $100 in included compute credits. GPU and storage rates depend on the resources used.

Compare E2B alternatives around your agent's actual requirements: continuous runtime, persistent files or memory, GPU access, deployment location, and cost at the concurrency you need.

Northflank is a strong fit when your requirements include:

• Long-running AI agent sandboxes without a fixed session cutoff
• Concurrent execution in custom environments
• CPU and GPU workloads
• Persistent files between tasks
• Sandbox execution inside your own infrastructure

Its sandbox APIs and deployment options let teams run varied agent workloads on managed cloud or in their own environment. Daytona, Vercel Sandbox, and Modal offer other combinations of lifecycle controls, persistence, and managed execution.