Capybara
Ruby library for automated tests that drive a web app the way a real user would.
- Stars
- 10.2k
- Forks
- 1.5k
- Licence
- MIT
- Language
- Ruby
- Last update
- 1 months ago
- Type
- Library
What it is
Capybara is a Ruby library for writing acceptance tests for web applications. Tests use readable commands like clicking a button or filling in a field, and Capybara simulates a user interacting with the app. It can run against a fast headless driver or a real browser through Selenium, and works out of the box with Rails and Rack apps.
- Write a test that signs a user in by filling in a form and checking for a success message
- Run the same test suite headless for speed or in a real browser for JavaScript-heavy pages
- Test forms, links, buttons, and modals in a web app
Great for
- Ruby and Rails developers writing feature or system tests
- Teams that want the same test code to run headless or in a real browser
- Projects already using RSpec, Cucumber, Minitest, or Test::Unit
Not ideal for
- Teams not using Ruby, since the library is written for Ruby test frameworks
- Projects that only need unit tests of internal code rather than user-facing behavior
- Anyone needing WebKit support out of the box, since it is provided only through an external gem
How to get it
- 1
Install with a package manager
You'll need: Ruby 3.0.0 or later · Bundler
Add the gem to your Gemfile, then install
gem 'capybara'Install dependencies
bundle install - 2
Run it
- Add gem 'capybara' to your Gemfile and run bundle install
- Require capybara in your test helper (for example capybara/rails for Rails, or capybara/rspec for RSpec)
- For a Rack app that is not Rails, set Capybara.app to your Rack app
- Write a feature spec with type: :feature that visits a page and checks for content
- 3
Get the most out of it
- Tag tests with js: true or a driver option to switch to a browser driver for JavaScript pages
- Use within to scope actions to a section of the page
- Configure Capybara.server = :puma to match Rails defaults, as the README suggests
- Use the Capybara DSL with Cucumber by tagging scenarios @javascript
Downloads
Strengths
- Readable API that mirrors how a real user interacts with the page
- Driver can be switched between headless and browser without changing tests, per the README
- Built-in waiting for asynchronous page changes, so tests need no manual sleeps
Trade-offs
- JavaScript testing requires a real browser driver such as Selenium, which adds setup
- WebKit support depends on a separate external gem
- Requires Ruby 3.0.0 or later
How it compares
| Project | Stars | Type | Level | Updated | Best for |
|---|---|---|---|---|---|
| capybara (this) | 10.2k | Library | intermediate | 1 months ago | Ruby and Rails developers writing feature or system tests |
| cypress | 51k | Dev tool | beginner | 4 days ago | Developers who want automated browser tests for a web application |
Stats synced from GitHub. The assessment above was drafted with AI from the project's README on 2026-10-29 and may miss recent changes — check the README before relying on a command. MIT licence: free to use, modify and distribute, including commercially, as long as you keep the copyright notice.