# Deploy Sinatra on Light Cloud

> Sinatra is a small Ruby library for web apps and APIs. Light Cloud detects it from sinatra in the Gemfile. It runs as a container that scales with traffic and down to zero when idle.

## Sinatra at a glance

- **Detected from:** `sinatra` in the `Gemfile`
- **Runs as:** Container that scales with traffic and to zero when idle
- **Ruby:** Ruby 3.2
- **Start command:** `bundle exec rackup` when there is a `config.ru`, otherwise `ruby app.rb`
- **Port:** 3000

## How to deploy Sinatra

1. **Bring the code.** Pick a repository, upload a folder, or ask Claude Code or GitHub Copilot to put it online.
2. **Sinatra, detected.** The files are read and the build is filled in. Every setting can be changed by hand.
3. **Built into a container.** An image is built and started, listening on the port the app expects.
4. **Live.** A light-cloud.io URL in minutes, a preview URL for every branch, and logs and metrics beside it.

## More on Ruby

- [Ruby](https://light-cloud.com/runtimes/ruby): Rack apps

## Add a database

- [PostgreSQL](https://light-cloud.com/databases/postgresql): Shared or dedicated

## Questions

### How do I deploy Sinatra?

Connect the repository, upload the folder, or ask Claude Code or GitHub Copilot to deploy it. Light Cloud reads the files, builds Sinatra and returns a live URL in minutes, with a preview URL for every branch.

### How much does it cost to host Sinatra?

The Free plan runs up to 3 server apps with $1 of usage a month and no card. A container is billed by the hour only while it runs, so an idle app costs nothing and a quiet one uses about $0.10 a month. Paid plans start at $5 a month with $5 of usage included.

### Can a Sinatra app use a database?

Yes. Create a PostgreSQL database in the same project and set its connection string as DATABASE_URL. Databases come with paid plans, from $5 a month.

### Can I use my own Dockerfile instead?

Yes. A Dockerfile at the root of the repository always wins over detection: it is built as is and runs as a container.

Docs: https://docs.light-cloud.com/platform/frameworks/sinatra
Page: https://light-cloud.com/frameworks/sinatra
Deploy Sinatra: https://console.light-cloud.com/new?repo=https://github.com/light-cloud-templates/sinatra-api-starter
Start free, no card: https://console.light-cloud.com/signup