Quickstart
1
Build the SSH template
Define a template that includes an OpenSSH server for SSH access and websocat for forwarding WebSocket-based connections:Now build it:
// template.ts
import { Template, waitForPort } from 'novita-sandbox/code-interpreter'
export const template = Template()
.fromUbuntuImage('25.04')
.aptInstall(['openssh-server'])
.runCmd([
'curl -fsSL -o /usr/local/bin/websocat https://github.com/vi/websocat/releases/latest/download/websocat.x86_64-unknown-linux-musl',
'chmod a+x /usr/local/bin/websocat',
], { user: 'root' })
.setStartCmd('sudo websocat -b --exit-on-eof ws-l:0.0.0.0:8081 tcp:127.0.0.1:22', waitForPort(8081))
# template.py
from novita_sandbox.code_interpreter import Template, wait_for_port
template = (
Template()
.from_ubuntu_image("25.04")
.apt_install(["openssh-server"])
.run_cmd([
"curl -fsSL -o /usr/local/bin/websocat https://github.com/vi/websocat/releases/latest/download/websocat.x86_64-unknown-linux-musl",
"chmod a+x /usr/local/bin/websocat",
], user="root")
.set_start_cmd("sudo websocat -b --exit-on-eof ws-l:0.0.0.0:8081 tcp:127.0.0.1:22", wait_for_port(8081))
)
// build.ts
import { Template, defaultBuildLogger } from 'novita-sandbox/code-interpreter'
import { template as sshTemplate } from './template'
await Template.build(sshTemplate, 'ssh-ready', {
cpuCount: 2,
memoryMB: 2048,
onBuildLogs: defaultBuildLogger(),
})
# build.py
from novita_sandbox.code_interpreter import Template, default_build_logger
from template import template as ssh_template
Template.build(ssh_template, "ssh-ready",
cpu_count=2,
memory_mb=2048,
on_build_logs=default_build_logger(),
)
2
Launch a sandbox from that template
import { Sandbox } from 'novita-sandbox/code-interpreter'
const sbx = await Sandbox.create('ssh-ready')
console.log(sbx.sandboxId)
from novita_sandbox.code_interpreter import Sandbox
sbx = Sandbox.create("ssh-ready")
print(sbx.sandbox_id)
3
Connect from your local machine
# Install websocat
brew install websocat
# Connect to your sandbox
ssh -o 'ProxyCommand=websocat --binary -B 65536 - wss://8081-%h.sandbox.novita.ai' user@<sandbox-id>
# Install websocat
sudo curl -fsSL -o /usr/local/bin/websocat https://github.com/vi/websocat/releases/latest/download/websocat.x86_64-unknown-linux-musl
sudo chmod a+x /usr/local/bin/websocat
# Connect to your sandbox
ssh -o 'ProxyCommand=websocat --binary -B 65536 - wss://8081-%h.sandbox.novita.ai' user@<sandbox-id>
How it works
Websocat acts as the proxy, and SSH connections are forwarded over WebSocket through the sandbox’s exposed ports.┌───────────────────────────────────────────────────────────┐
│ Your Machine │
│ ┌──────────┐ ProxyCommand ┌──────────────────┐ │
│ │ SSH │ ────────────────── │ websocat │ │
│ │ Client │ │ (WebSocket) │ │
│ └──────────┘ └─────────┬────────┘ │
└────────────────────────────────────────────┼──────────────┘
│
wss://8081-<sandbox-id>.sandbox.novita.ai
│
┌────────────────────────────────────────────┼──────────────┐
│ Novita Sandbox ▼ │
│ ┌──────────────────┐ │
│ │ websocat │ │
│ │ (WS → TCP:22) │ │
│ └─────────┬────────┘ │
│ │ │
│ ┌─────────▼────────┐ │
│ │ SSH Server │ │
│ │ (OpenSSH) │ │
│ └──────────────────┘ │
└───────────────────────────────────────────────────────────┘