The Fuchsia Test Runner Framework enables developers to build tests for components using a variety of languages and runtimes and execute them on a target device. The framework provides test runner components that implement the fuchsia.test.Suite protocol and integrate with common language-specific testing frameworks such as GoogleTest (C++).

The test_manager component is responsible for running tests on a Fuchsia device. It examines components implementing the test suite protocol and launches them as child components. This means that test_manager is also responsible for providing capabilities to each test suite, creating what is commonly called the test realm.

![Diagram showing how the Test Runner Framework provides interfaces for developers to expose test suites and for developer tools to execute tests on the Fuchsia device.] (/docs/get-started/images/components/test-realm.png){: width=“714”}

Developer tools such as ffx test communicate with the test_manager on the device to execute test suites and retrieve the results.