Serverless Apps

Serverless apps run entirely on Crowdin infrastructure. You write the UI, and Crowdin hosts and runs the app, so there is no backend to deploy or maintain. Serverless apps support UI modules such as project dashboards, editor panels, and menu extensions, and call the Crowdin API on behalf of the person using the app.

You build a serverless app with the Crowdin Serverless Apps SDK and its CLI. The starter templates come with TypeScript, React, a UI kit styled to match Crowdin, and an i18n runtime.

The Serverless Apps SDK has its own documentation with templates, guides, and an API reference:

Serverless Apps SDKTemplates, SDK guides, CLI commands, and API reference.

Building a Serverless App

Everything happens in the terminal: scaffold an app from a template, run it live inside Crowdin, and publish it.

npm install --global @crowdin/serverless-apps-cli
crowdin-serverless-apps login
crowdin-serverless-apps create my-app
crowdin-serverless-apps dev
crowdin-serverless-apps preview
crowdin-serverless-apps publish

The published app is installed in your account, and the manifest controls who can use it.

Read more about each step in the Quick Start.

When to Build a Self-Hosted App Instead

Serverless apps cover the UI side of Crowdin. When your app needs server-side logic (for example, file processing, AI providers, custom MT engines, or webhook handling), build it as a self-hosted app. The same applies when your app combines an interface with server-side logic: self-hosted apps can include UI modules as well.

A self-hosted app also works with the Crowdin API differently: it makes calls as the account that installed it, not as the person using it. Choose this path as well if you plan to publish the app on the Crowdin Store.

Read more about building a self-hosted app in the Quick Start.