Custom templates
A template sets the base image, environment variables, files to copy, setup commands and a start command.
Scaffold with the CLI#
e2b template initOr set it up by hand (requires E2B SDK 2.3.0 or newer):
1
Install the packages
npm install e2b dotenv or pip install e2b python-dotenv, and put E2B_API_KEY=e2b_*** in .env.
2
Define the template
Describe the image in template.ts or template.py.
3
Write a build script
One script per environment — a dev tag and a production tag.
4
Build
npx tsx build.dev.ts or python build_dev.py.
5
Start sandboxes from it
Pass the tag to Sandbox.create().
Define#
// template.ts
import { Template, waitForTimeout } from 'e2b'
export const template = Template()
.fromBaseImage()
.setEnvs({
HELLO: 'Hello, World!',
})
.setStartCmd('echo $HELLO', waitForTimeout(5_000))# template.py
from e2b import Template, wait_for_timeout
template = (
Template()
.from_base_image()
.set_envs({"HELLO": "Hello, World!"})
.set_start_cmd("echo $HELLO", wait_for_timeout(5_000))
)Build#
// build.dev.ts
import 'dotenv/config'
import { Template, defaultBuildLogger } from 'e2b'
import { template } from './template'
await Template.build(template, 'template-tag-dev', {
cpuCount: 1,
memoryMB: 1024,
onBuildLogs: defaultBuildLogger(),
})# build_dev.py
from dotenv import load_dotenv
from e2b import Template, default_build_logger
from template import template
load_dotenv()
Template.build(
template,
'template-tag-dev',
cpu_count=1,
memory_mb=1024,
on_build_logs=default_build_logger(),
)Builds can run for up to 1 hour. CPU, memory, disk and concurrent-build limits depend on your plan.
Use#
import { Sandbox } from 'e2b'
const dev = await Sandbox.create('template-tag-dev')
const prod = await Sandbox.create('template-tag')from e2b import Sandbox
dev = Sandbox.create(template="template-tag-dev")
prod = Sandbox.create(template="template-tag")Many similar templates#
Layer per-customer or per-project config on a shared base with fromTemplate() / from_template(). Builds reuse the base's cached layers, so they finish faster.
import { Template } from 'e2b'
export const template = Template()
.fromTemplate('my-base-template')
.copy('./customers/acme', '/app/config')
.setEnvs({ CUSTOMER_ID: 'acme' })from e2b import Template
template = (
Template()
.from_template("my-base-template")
.copy("./customers/acme", "/app/config")
.set_envs({"CUSTOMER_ID": "acme"})
)