Fly.io Sprites
Persistent, hardware-isolated Linux computers for AI agents with a durable 100 GB disk, checkpoints, and no compute charges while idle. The most natural “persistent computer per agent” model, with idle-free billing.
Overview
Sprites, launched in January 2026, are Fly.io’s take on “computers for agents” rather than throwaway sandboxes. Each Sprite is a hardware-isolated microVM with a durable 100 GB disk, a public or private HTTPS URL and no lifetime limit. It sleeps after about 30 seconds idle and wakes on demand, and you pay only storage while it sleeps.
Checkpoints take copy-on-write snapshots of the whole filesystem in about a second, so an agent can try something risky and roll back.
Notable
- Launched January 2026.
- Offers a remote MCP server and setups for Claude Managed Agents and Cursor Cloud Agents.
Fly.io Sprites specifications
| Attribute | Details |
|---|---|
| Isolation | Dedicated microVM with hardware-level isolation (Fly docs); reported to be Firecracker-based |
| Deployment | Hosted platform |
| Open source | No (SDKs MIT) |
| SDKs and interfaces | JavaScript/TypeScript, Go, Python, Elixir |
| Cold start (vendor claim) | Warm wake 100–500 ms with processes preserved; cold wake 1–2 s (vendor docs) |
| Max session length | No lifetime limit — a Sprite persists until destroyed and sleeps after ~30 s idle |
| Persistence | 100 GB durable disk per Sprite that survives sleep; copy-on-write checkpoints (~1 s) with restore; memory preserved on warm pause |
| GPU | No GPU option documented |
| Networking | HTTPS URL per Sprite (org-private by default); outbound open by default with optional DNS-based domain allow/deny policy; connectors broker API credentials |
| Pricing | Per second, compute only while active: $0.0385 per CPU-hour + $0.021875 per GB-hour memory; storage billed while idle |
| Free tier | $30 trial credit for new organizations |
| Compliance | Fly.io is SOC 2 Type 2; HIPAA BAA and DPA available (company-wide) |
| Regions | Not documented |
Facts from Fly.io Sprites’s public documentation, verified November 8, 2026. Performance numbers are vendor claims.
Strengths and trade-offs
Strengths
- You want a persistent computer per agent or per user
- Your agents are idle most of the time and you want to pay only for active compute
- You want fast checkpoints and rollback
- You want Elixir or Go SDKs
Trade-offs
- No GPUs
- Fixed 8 vCPU / 100 GB shape; memory platform-managed
- Hosted only — no self-hosting or BYOC
Best for: Long-running, stateful agent computers that should cost nothing while idle.
Where Fly.io Sprites ranks
How Fly.io Sprites compares
| Sandbox | Isolation | Open source | Self-host / BYOC | Cold start (vendor) | Max session | Snapshots / pause | GPU | SDKs |
|---|---|---|---|---|---|---|---|---|
| Fly.io Sprites | MicroVM | No | No / No | 0.1–2 s wake | Unlimited | Yes / Yes | No | JavaScript/TypeScript, Go, Python, Elixir |
| Daytona | Containers or VMs | No | Not documented / Yes | <90 ms | Unlimited | Yes / Yes | Yes | Python, TypeScript, Ruby, Go, Java |
| E2B | Firecracker microVM | Yes | Yes / Yes | Not documented | 1 h / 24 h (Pro) | Yes / Yes | No | Python, JavaScript/TypeScript |
| Vercel Sandbox | Firecracker microVM | No | No / No | Milliseconds (claim) | 24 h (Pro) | Yes / Yes | Not documented | JavaScript/TypeScript, Python |
| Morph Cloud | VM | No | No / Not documented | <250 ms (restore) | Configurable | Yes / Yes | Not documented | Python, TypeScript |
| Together Code Sandbox | MicroVM | No | No / Not documented | 0.5 s (snapshot) | Until terminated | Yes / Yes | Not documented | Python, TypeScript |
Head-to-head: E2B vs Fly.io Sprites · Daytona vs Fly.io Sprites · Modal Sandboxes vs Fly.io Sprites · Vercel Sandbox vs Fly.io Sprites · Cloudflare Sandbox SDK vs Fly.io Sprites · Blaxel vs Fly.io Sprites
Frequently asked questions
What is Fly.io Sprites?
How does Fly.io Sprites isolate code?
Is Fly.io Sprites open source?
How much does Fly.io Sprites cost?
What are the best Fly.io Sprites alternatives?
Sources
Cite this page
Agent Sandboxes. (2026). Fly.io Sprites. agentsandboxes.org. Last reviewed November 8, 2026. https://agentsandboxes.org/sandboxes/fly-sprites/
Found an error or a missing sandbox? Submit a correction — every entry links to the sources it relies on.