Beam Sandboxes
Serverless AI compute platform whose sandboxes are gVisor-isolated containers with memory snapshots, optional GPUs and an open-source, self-hostable runtime. A cost-effective GPU sandbox with an open runtime; best for trusted or semi-trusted code.
Overview
Beam is a serverless GPU platform whose sandboxes run as gVisor-isolated containers with millisecond billing, memory snapshots and attachable GPUs. Its runtime, beta9, is open source under AGPL-3.0 and can be self-hosted on Kubernetes, with a BYOC option for running in your own cloud.
Beam is candid that gVisor is a lighter boundary than microVMs and points users with hostile multi-tenant code toward microVM providers.
Notable
- Backed by Y Combinator and others listed on its site.
Beam Sandboxes specifications
| Attribute | Details |
|---|---|
| Isolation | gVisor + runc containers (Beam recommends microVM providers for hostile multi-tenant code) |
| Deployment | Hosted platform · BYOC available · Self-hostable |
| Open source | Yes (AGPL-3.0 (beta9 runtime)) |
| SDKs and interfaces | Python, TypeScript |
| Cold start (vendor claim) | About half a second; 100 concurrent sandboxes in 0.55 s (vendor claim) |
| Max session length | 600 s default lifetime, extendable or disabled |
| Persistence | Filesystem snapshots, memory snapshots, pause/restore, volumes and durable disks |
| GPU | Yes — GPUs attachable to sandboxes (e.g. RTX 4090 $0.69/hour) |
| Networking | Public preview URLs via expose_port (add your own auth); runtime egress policies |
| Pricing | Billed by the millisecond: performance tier $0.05/vCPU-hour + $0.01/GiB-hour; cheaper shared and spot tiers; plans from $20/month |
| Free tier | Developer plan $20/month includes $20 of credit |
| Compliance | SOC 2 Type II |
| Regions | Not documented |
Facts from Beam Sandboxes’s public documentation, verified November 8, 2026. Performance numbers are vendor claims.
Strengths and trade-offs
Strengths
- You want GPUs inside sandboxes at low rates
- You want an open-source runtime you can self-host
- You want spot and shared tiers for cheap batch work
Trade-offs
- gVisor rather than microVM isolation
- AGPL-3.0 licence may not suit all companies
- Preview URLs need your own authentication
Best for: Teams that want an open-source, self-hostable sandbox runtime with GPU access.
Where Beam Sandboxes ranks
How Beam Sandboxes compares
| Sandbox | Isolation | Open source | Self-host / BYOC | Cold start (vendor) | Max session | Snapshots / pause | GPU | SDKs |
|---|---|---|---|---|---|---|---|---|
| Beam Sandboxes | gVisor | Yes | Yes / Yes | ~0.5 s | Configurable | Yes / Yes | Yes | Python, TypeScript |
| Modal Sandboxes | gVisor or VM | No | No / Not documented | <1 s | Up to 24 h | Yes / Yes | Yes | Python, JavaScript/TypeScript, Go |
| Northflank Sandboxes | Cloud Hypervisor microVM | No | No / Yes | <1 s | Unlimited | Not documented / Yes | Yes | JavaScript/TypeScript, Python |
| Daytona | Containers or VMs | No | Not documented / Yes | <90 ms | Unlimited | Yes / Yes | Yes | Python, TypeScript, Ruby, Go, Java |
| Koyeb Sandboxes | MicroVM | No | No / Not documented | Not documented | Up to 24 h | Not documented / Not documented | Yes | Python, JavaScript/TypeScript |
Head-to-head: Beam Sandboxes vs Modal Sandboxes
Frequently asked questions
What is Beam Sandboxes?
How does Beam Sandboxes isolate code?
Is Beam Sandboxes open source?
How much does Beam Sandboxes cost?
What are the best Beam Sandboxes alternatives?
Sources
Cite this page
Agent Sandboxes. (2026). Beam Sandboxes. agentsandboxes.org. Last reviewed November 8, 2026. https://agentsandboxes.org/sandboxes/beam/
Found an error or a missing sandbox? Submit a correction — every entry links to the sources it relies on.