Secure operating system without a sandbox.
A lightweight library for giving your agents an OS.No containers, no VMs — just file system, networking, bash, Python, and Node.
A lightweight computer as a library.
- agentOS boots a small virtual OS per agent: kernel, file system, processes, sockets, deny-by-default permissions.
- It runs on WASM, the same sandboxing primitive shipped in every browser tab.
- No hypervisor, no containers, no network gap.
npm install @rivet-dev/agentos @agentos-software/pi
Before: a sandbox service
Your backend
network
Sandbox1 GiB
Sandbox1 GiB
Sandbox1 GiB
After: agentOS
Your backend22–131 MB per agent
OSOSOSOSOSOSOSOSOSOSOSOSOSOSOSOSOSOSOSOSOSOS
Sandbox services are infrastructure. agentOS is a library.
Sandbox services run VM fleets across a network gap, behind vendor accounts and API keys. agentOS runs in your process, in your VPC or on-prem.
agentOSSandbox service
Where agents runInside your backend processOn external infrastructure, across an untrusted network boundary
IsolationWebAssemblyMicroVM
Setupnpm installVendor account and API keys
Custom integrationsDirect JS function callsCustom API + authentication
CredentialsNever leave the hostInjected into the sandbox
What staying in-process saves.
Benchmark documentCold Start
0xfaster
agentOSWhat's measured: Time from requesting an execution to first code running.
Why the gap: agentOS runs agents in-process — WASM inside your host. No VM to boot, no network hop, no disk image. Sandboxes must boot an entire environment, allocate memory, and establish a network connection before code can run.
Sandbox baseline: E2B, the fastest mainstream sandbox provider as of March 30, 2026.
agentOS: Median of 10,000 runs (100 iterations x 100 samples) on Intel i7-12700KF.4.8 ms
Why the gap: agentOS runs agents in-process — WASM inside your host. No VM to boot, no network hop, no disk image. Sandboxes must boot an entire environment, allocate memory, and establish a network connection before code can run.
Sandbox baseline: E2B, the fastest mainstream sandbox provider as of March 30, 2026.
agentOS: Median of 10,000 runs (100 iterations x 100 samples) on Intel i7-12700KF.4.8 ms
Fastest sandbox440 ms
Memory Per Instance?Sandboxes reserve idle RAM per agent.
0xsmaller
agentOSWhat's measured: Memory footprint added per concurrent execution.
Why the gap: In-process isolates share the host's memory. Each additional execution only adds its own heap and stack. Sandboxes allocate a dedicated environment with a minimum memory reservation, even if the code inside uses far less.
Sandbox baseline: Daytona, the cheapest mainstream sandbox provider as of March 30, 2026. Default sandbox: 1 vCPU + 1 GiB RAM.
agentOS: ~22 MB for the minimal shell workload under sustained load.~22 MB
Why the gap: In-process isolates share the host's memory. Each additional execution only adds its own heap and stack. Sandboxes allocate a dedicated environment with a minimum memory reservation, even if the code inside uses far less.
Sandbox baseline: Daytona, the cheapest mainstream sandbox provider as of March 30, 2026. Default sandbox: 1 vCPU + 1 GiB RAM.
agentOS: ~22 MB for the minimal shell workload under sustained load.~22 MB
Cheapest sandbox~1024 MB
Cost Per Execution-Second?Assumes one agent per sandbox, needed for isolation.
0xcheaper
agentOSWhat's measured:
Why it's cheaper: Each execution uses ~22 MB instead of a ~1024 MB sandbox minimum. And you run on your own hardware, which is significantly cheaper than per-second sandbox billing.
Sandbox baseline: Daytona, the cheapest mainstream sandbox provider as of March 30, 2026. Default sandbox: 1 vCPU + 1 GiB RAM at $0.0504/vCPU-h + $0.0162/GiB-h.
agentOS: ~22 MB baseline per execution, assuming 70% utilization (industry-standard HPA scaling threshold). Select a hardware tier above to compare.$0.000000073/s
server price per second / concurrent executions per serverWhy it's cheaper: Each execution uses ~22 MB instead of a ~1024 MB sandbox minimum. And you run on your own hardware, which is significantly cheaper than per-second sandbox billing.
Sandbox baseline: Daytona, the cheapest mainstream sandbox provider as of March 30, 2026. Default sandbox: 1 vCPU + 1 GiB RAM at $0.0504/vCPU-h + $0.0162/GiB-h.
agentOS: ~22 MB baseline per execution, assuming 70% utilization (industry-standard HPA scaling threshold). Select a hardware tier above to compare.$0.000000073/s
Cheapest sandbox$0.000018/s
Everything the agent needs is already there.
File system, execution, tools, approvals, and memory live in the same process as your code.
agentos vm · /home/agentos
The agent writes one program instead of a chain of tool calls.
git, ripgrep, sqlite3, and browsers install straight into the VM.
Built for every kind of agent.
Orchestration is just code.
Sessions, workflows, multiplayer, and approvals are objects in your code, not services you deploy.
agents.ts
import { createClient } from "@rivet-dev/agentos/client";
import type { registry } from "./server";
const client = createClient<typeof registry>({ endpoint: "http://localhost:6420" });
const agent = client.vm.getOrCreate("my-agent");
const connection = agent.connect();
// Stream events (tool calls, text output, etc.)
connection.on("sessionEvent", (event) => console.log(event));
// Create a session and send a prompt
await agent.openSession({ agent: "pi", env: { ANTHROPIC_API_KEY: process.env.ANTHROPIC_API_KEY! } });
await agent.prompt({
content: [{ type: "text", text: "Write a Python script that calculates pi" }],
});Observability
Watch the transcript, filesystem, and processes of a live VM. Every event also streams to your code.
Ships wherever your backend ships.
Each VM is a Rivet Actor with durable state. Your existing deployment works.
Turn your backend into the agent platform.
Open source under Apache 2.0. One npm install away.