Definition
A compute primitive that runs untrusted or AI-generated code in a hardware-level isolation boundary (microVM), with dedicated per-instance CPU, memory, and networking — as opposed to process-level or container-level isolation that shares a host kernel.
Why it's a canonical
This is the category CreateOS plays in when they pitch "agent sandbox." It's not a feature of the AI builders in this vault (Replit and Anything.com run untrusted app code but don't expose the sandbox primitive directly). Fly.io is the only competitor here with a headline product — Flydotio - Sprites.
The broader competitive set for this primitive: E2B, Daytona, Modal, Runloop, Cloudflare Workers, Vercel Sandbox, Blaxel — and CreateOS. The OpenAI Agents SDK default provider list (as of CreateOS Addendum 3) includes six of these; Fly.io / Sprites is not yet on the list but is pitching into it.
Comparison (this vault)
| Fly.io | Replit | Anything.com | |
|---|---|---|---|
| Product name | Flydotio - Sprites | — (agents run inside Replit's own runtime) | — |
| Isolation level | Hardware (microVM) | Not exposed | Not exposed |
| Per-instance dedicated resources | ✅ | N/A | N/A |
| Named for AI workloads | ✅ "Run AI-generated code in complete safety" | Agent runs in Replit's own infra | Agent runs in Anything's infra |
| API for external callers | ❓ (sandbox-as-a-service implied) | ❌ | ❌ |
Key differences
Builder-category vs. runtime-category. Replit and Anything.com run agents inside their own closed stack — the sandbox is an internal implementation detail. Fly.io pitches Sprites to other companies' agents (via SDK, via OpenAI Agents SDK integration, via direct developer adoption). Two adjacent markets, one substrate.
What CreateOS needs to know
- Sprites is a real competitor for the agent-runtime slot — not Replit, not Anything.com.
- OpenAI Agents SDK default-provider listing is the brass ring. CreateOS's internal brief flags this explicitly; Fly.io is pitching into the same listing.
- The earning-agent wedge still holds. Sprites has no equivalent to MPP. Fly cannot add on-chain payments without entering money movement.
Our take
To be filled by the user.
Sources
- Flydotio - Sprites
- fly.io homepage (Sprites section)