# Server-Side Extensions

Server-side extensions give you direct control over the underlying .NET framework and Umbraco's internal services. Use these guides to build custom functionality at any layer of the stack.

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><strong>Cache &#x26; Distributed Cache</strong></td><td>Implement application caching in single-server and load-balanced environments.</td><td><a href="/pages/WJ8n9ZZ31e6Erd9v7k30">/pages/WJ8n9ZZ31e6Erd9v7k30</a></td></tr><tr><td><strong>Custom Routing</strong></td><td>Configure custom routes and URL handling in Umbraco CMS.</td><td><a href="/pages/1mgeTAtYnYPfDV1J02c1">/pages/1mgeTAtYnYPfDV1J02c1</a></td></tr><tr><td><strong>Language Files &#x26; Localization</strong></td><td>Manage localization and language files for your Umbraco site.</td><td><a href="/pages/UbsRwWsZxNICV2Colzxo">/pages/UbsRwWsZxNICV2Colzxo</a></td></tr><tr><td><strong>Management</strong></td><td>Interact with Umbraco data through CRUD operations and the persistence layer.</td><td><a href="/pages/QDKo6c3fRU6FN33vSlWR">/pages/QDKo6c3fRU6FN33vSlWR</a></td></tr><tr><td><strong>Using Notifications</strong></td><td>Subscribe to and handle Umbraco notifications to react to content and application events.</td><td><a href="/pages/0rnSF7ChFP0fMqWknSXp">/pages/0rnSF7ChFP0fMqWknSXp</a></td></tr><tr><td><strong>Services and Helpers</strong></td><td>Access Umbraco data and functionality through the core services and helpers.</td><td><a href="/pages/1PsHaY9uI9ahZ6uyiNzr">/pages/1PsHaY9uI9ahZ6uyiNzr</a></td></tr></tbody></table>

## Additional Resources

* [API Documentation](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/api-documentation.md) - generate and browse API documentation for your Umbraco project.
* [API Versioning and OpenAPI](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/api-versioning-and-openapi.md) - version your APIs and configure OpenAPI documentation.
* [Backoffice Search](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/backoffice-search.md) - customise search in the Umbraco backoffice.
* [Content Type Filters](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/content-type-filters.md) - restrict the content types available to editors.
* [Creating a Custom Database Table](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/database.md) - add and manage custom database tables in Umbraco.
* [Custom File Systems](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/filesystemproviders.md) - create custom file systems using the IFileSystem interface.
* [Custom Swagger API](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/custom-swagger-api.md) - configure custom Swagger documents for your APIs.
* [Embedded Media Providers](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/embedded-media-providers.md) - add support for embedding media from external providers.
* [Flag Providers](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/flag-providers.md) - expose flag information in Management API responses.
* [JSON Serialization](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/json-serialization.md) - configure JSON serialization behavior in Umbraco.
* [Scheduling](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/scheduling.md) - run scheduled background tasks in Umbraco.
* [Server Events From SignalR](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/server-events.md) - push real-time server events to the browser using SignalR.
* [UmbracoMapper](/umbraco-cms/18.latest/extend-your-project/server-side-extensions/mapping.md) - map between objects using UmbracoMapper.


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