Ephemeral Box - Upstash Documentation

EphemeralBox is a lightweight, short-lived sandbox that provides only exec and file operations. It's designed for quick, disposable compute tasks where a full Box (with agent, git, snapshots, etc.) is unnecessary.

Creation

box.ts

import { EphemeralBox } from "@upstash/box"const box = await EphemeralBox.create({  runtime: "node",  // "node" | "python" | "golang" | "ruby" | "rust"  ttl: 3600,        // seconds, max 259200 (3 days), default 259200  name: "my-ephemeral-worker",          // optional  networkPolicy: { mode: "allow-all" }, // optional})

box.py

from upstash_box import EphemeralBoxbox = EphemeralBox.create(    runtime="node",  # "node" | "python" | "golang" | "ruby" | "rust"    ttl=3600,        # seconds, max 259200 (3 days), default 259200    name="my-ephemeral-worker",            # optional    network_policy={"mode": "allow-all"},  # optional)

Key difference from Box.create(): Ephemeral boxes are ready immediately — no polling. The API returns with status: "idle" and the box is usable right away.

The request sends { ephemeral: true, ttl?, runtime? } to POST /v2/box.

Available API

Feature	Box	EphemeralBox
`exec.command()`	Yes	Yes
`exec.code()`	Yes	Yes
`exec.stream()`	Yes	Yes
`exec.streamCode()`	Yes	Yes
`files.read/write/list/upload/download`	Yes	Yes
`schedule.exec/prompt/list/get/pause/resume/delete`	Yes	Yes
`cd()` / `cwd`	Yes	Yes
`getStatus()`	Yes	Yes
`delete()`	Yes	Yes
`networkPolicy` / `updateNetworkPolicy()`	Yes	Yes
`expiresAt`	No	Yes
`agent.run()` / `agent.stream()`	Yes	No
`git.*`	Yes	No
`getPublicURL()` / `listPublicURLs()` / `deletePublicURL()`	Yes	No
`snapshot()` / `fromSnapshot()`	Yes	Yes
`pause()` / `resume()`	Yes	No
`configureModel()`	Yes	No
`logs()` / `listRuns()`	Yes	No

Properties

id — box identifier (e.g. "sweet-shark-26021")
expiresAt — Unix timestamp (seconds) when the box auto-deletes

How it differs from Box

Instant creation — no polling loop; the response is the ready box
Auto-expiry — boxes are automatically deleted after TTL; expiresAt tracks this
Reduced surface — only exec + files; no agent, git, public URLs, snapshots, pause/resume
Simpler config — EphemeralBoxConfig has only apiKey, runtime, ttl, name, networkPolicy, baseUrl, timeout, debug (no agent, git, env, skills, mcpServers)
Composition over inheritance — EphemeralBox wraps an internal Box and exposes only the relevant subset, so agent/git/etc. are not accessible even at runtime

Examples

Run a shell command

box.ts

const run = await box.exec.command("echo hello")console.log(run.result) // "hello"

box.py

run = box.exec.command("echo hello")print(run.result)  # "hello"

Execute inline code

box.ts

const result = await box.exec.code({  code: 'console.log(JSON.stringify({ sum: 1 + 2 }))',  lang: "js",})

box.py

result = box.exec.code(    code="import json; print(json.dumps({'sum': 1 + 2}))",    lang="python",)

File operations

box.ts

await box.files.write({ path: "data.json", content: '{"key":"value"}' })const content = await box.files.read("data.json")

box.py

box.files.write(path="data.json", content='{"key":"value"}')content = box.files.read("data.json")

Clean up early

Otherwise the box auto-deletes at expiresAt.

box.ts

await box.delete()

box.py

box.delete()

Exported types

EphemeralBox — the class
EphemeralBoxConfig — config for EphemeralBox.create()
EphemeralBoxData — extends BoxData with ephemeral: boolean and expires_at: number