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E2B vs Modal. Rows marked Differs have different values.

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E2B

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TypeStartupStartup
CategoriesDiffers
In one lineOpen-source sandboxes for running AI-generated code.Serverless cloud built for AI and agentic compute.
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Pros
  • User reportsUses Firecracker microVM isolation; one team building persistent dev machines said it had everything they needed.[1][2]
  • User reportsA common choice for per-session isolation in multi-tenant agent backends, including sandboxes that hold no credentials and sit behind gateways.[1][2]
  • User reportsIts API has become a target others build to: some self-hosted sandboxes advertise E2B compatibility.[1]
  • MetadataApache-2.0 and very actively maintained (about 14.6k stars, commits on 29 Oct 2026).[1]
  • User reportsSmall conveniences such as filesystem snapshots and images built in code make agent sandboxes easy to set up, according to a user.[1]
  • DocsSupports GPUs in sandboxes and checkpoint/restore on gVisor (per Modal's team on HN; a competitor also calls it the only sandbox provider with GPUs).[1][2]
  • User reportsUsers like its Pythonic decorator API and the $30 of free credits each month.[1][2]
  • User reportsSome teams run thousands of on-demand coding agents a day on it.[1]
Cons
  • User reportsOne builder found that managed sandboxes, E2B included, carry a large markup over bare-metal Docker or QEMU and handle long-running agents poorly.[1][2]
  • User reportsA competitor says E2B sandboxes feel less like full VMs and cannot run everything an EC2 instance can.[1]
  • User reportsSwitching sandbox providers is not trivial, so lock-in matters when you choose.[1]
  • User reportsResizing means stop, resize, start (about 3 seconds, and running processes are killed), so one user found its autoscaling worse than Daytona's.[1]
  • User reportsIt uses gVisor rather than Firecracker, and gVisor has missing or inaccurate syscalls that you may have to debug.[1][2]
  • User reportsUpstream cloud outages have reached it, as an incident on Modal's status page showed.[1]
  • User reportsA customer's sandbox was the launch point for a rogue-agent hack reported by Reuters (Modal says its platform was not compromised), so you need strict egress rules and permissions.[1]
Best forAgent products that need fast, strongly isolated code execution per session behind a widely supported API.Python teams that want GPU-capable sandboxes and serverless compute for agents on one platform.
Watch out forCheck session lifetime limits and per-second cost for long-running agents before you commit.Lock down egress and permissions yourself, and expect gVisor limits for Docker-heavy workloads.
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