crownest.dev · cloud sandboxes ]

Cloud sandboxes for coding agents.

Create isolated sandboxes, run commands, stream logs, expose authenticated previews, and persist artifacts - one clean SDK, CLI, and dashboard.

Start buildingRead the docs
agent
plan: analyze sales data
|
crownest sandbox · sbx_8f2a1c
agent connectedttl 60m
[..............]0.5 vCPU · 4 GiB
outputs
waiting for artifacts ...

the primitive ]

Four resources. One execution layer.

Sandboxes

Isolated Linux environments created from a template. Live in seconds, gone on TTL.

sandboxes.create({ template: "python" })

Commands

Run or stream any process. Exit codes, logs, and cancellation - all recorded.

commands.run("python main.py")

Previews

Expose a port from inside the sandbox as an authenticated URL on crownest.dev.

previews.create({ port: 8080 })

Artifacts

Promote the outputs that matter into durable, indexed storage that outlives the sandbox.

collect: ["/workspace/report.html"]

how it works ]

Create. Run. Collect. Kill.

01

Create

Spin up a sandbox from a template. It gets a workspace, a TTL, and nothing else.

02

Run

Execute commands, stream stdout, declare which outputs to collect on success.

03

Collect

Declared files become artifacts - durable, indexed, readable after teardown.

04

Kill

Tear it down (or let the TTL). Logs and artifacts stay; the tombstone is audited.

quickstart.ts
import { CrowNest } from "@crownest/sdk";

const client = new CrowNest({ apiKey: process.env.CROWNEST_API_KEY });

// 01 - create
const sandbox = await client.sandboxes.create({ template: "python" });

// 02 - run
const result = await sandbox.commands.run("python main.py", {
  collect: [{ path: "/workspace/report.html", name: "report.html" }],
  onStdout: (chunk) => process.stdout.write(chunk),
});

// 03 - collect
const artifacts = await sandbox.artifacts.list();

// 04 - kill
await sandbox.kill();

control plane ]

Real compute, without giving up control.

Isolated runtimes

Every sandbox is its own boxed Linux environment. Nothing shared, nothing leaked.

Scoped API keys

Singular resource:action scopes, restrictable to a project. Keys can't mint keys.

Quotas & budgets

compute_unit_seconds metered per second, with hard caps per bucket.

Audit events

Every create, run, revoke, and kill is recorded - tombstones included.

pricing ]

Per-second metering. No idle surprises.

$0.12 per sandbox-hour on the standard runtime, billed per second and pinned to your pricingVersion.

Free
$0one-time $10 credit
  • 2 concurrent sandboxes
  • 60 min max sandbox lifetime
  • Authenticated previews
  • Community support
Hobbycore tier
$20/mo · includes $25 usage
  • Higher concurrency
  • Full SDK, CLI & REST API
  • Artifact storage included
  • Per-second metered overage
Pro
from $100/mo · volume credit
  • Highest concurrency
  • Longer-lived sandboxes
  • Project-restricted API keys
  • Priority support