| # Components |
| |
| Components are the basic unit of executable software on Fuchsia. |
| |
| Note: This section contains documentation about components using the modern |
| component framework ([Components v2][glossary-components-v2]). |
| The Fuchsia platform team is currently [migrating legacy components][migration] |
| to the modern component framework. |
| For details on legacy components, see [Legacy components][legacy-components]. |
| |
| ## Architectural concepts |
| |
| - [Introduction](introduction.md): Understanding components and the component |
| framework. |
| - [Component manager](component_manager.md): The runtime. |
| - [Declarations](declarations.md): Describe components themselves. |
| - [Lifecycle](lifecycle.md): Component instance progression from creation to |
| destruction. |
| - [Topology](topology.md): The relationships among component instances. |
| - [Realms](realms.md): Sub-trees of the component instance topology. |
| - [Monikers](monikers.md): Identifiers for component instances based on |
| the component topology. |
| |
| ## Developing components |
| |
| - [Capabilities](capabilities/README.md): Different types of capabilities and |
| how to route them between components. |
| - [Component manifests](component_manifests.md): How to define a component for |
| the framework. |
| - [Component URLs][doc-component-urls] are URLs that identify components. |
| - [ELF runner](elf_runner.md): How to launch a component from an ELF file. |
| Typically useful for developing system components in C++, Rust, or Go. |
| |
| ## Extending the component framework |
| |
| - [Runners](capabilities/runners.md): Instantiate components; add support for more |
| runtimes. |
| - [Resolvers](capabilities/resolvers.md): Find components from URLs; add support for |
| methods of software packaging and distribution. |
| |
| ## Diagnostics |
| |
| - [Hub](hub.md): A live view of the component topology at runtime. |
| |
| ## Testing |
| |
| - [Test components][test-components]: |
| defining components that implement tests and running them. |
| - [Test Runner Framework][trf]: |
| writing idiomatic tests in different languages that use common testing frameworks. |
| - [Complex topologies and integration testing][integration-testing]: |
| testing interactions between multiple components in isolation from the rest of the |
| system. |
| - [OpaqueTest](opaque_test.md): Hermetic testing framework (DEPRECATED). |
| |
| ## Internals |
| |
| - [Component Framework design principles](design_principles.md) |
| - [Component manifest design principles][rfc0093] |
| - [Components vs. processes](components_vs_processes.md): how the concepts differ. |
| |
| [doc-component-urls]: /docs/concepts/components/component_urls.md |
| [glossary-components-v2]: /docs/glossary.md#components-v2 |
| [legacy-components]: /docs/concepts/components/v1/README.md |
| [migration]: /docs/contribute/open_projects/components/migration.md |
| [rfc0093]: /docs/contribute/governance/rfcs/0093_component_manifest_design_principles.md |
| [test-components]: /docs/concepts/testing/v2/test_component.md |
| [trf]: /docs/concepts/testing/v2/test_runner_framework.md |
| [integration-testing]: /docs/concepts/testing/v2/integration_testing.md |
