Nucleus is designed to facilitate the development of web applications and other extensions. Users install extensions from within the application. .NET developers can build web applications and extend the presentation layer (layouts and containers), site functionality (web applications and modules), the search system, file system providers, and more.

Our library of extensions includes modules for content management and presentation, support for single sign-in (SSO) using OAUTH and SAML, SEO enhancement, file system providers for Azure Storage and Amazon S3, and more.

Layouts and containers control the visual presentation of modules on a page. Layouts and Containers combine Razor, HTML and CSS.  Nucleus ships with a set of container and layouts, and our Developer Tools provide templates to help you to build your own. Bootstrap and Nucleus built-in CSS classes are always available.

Use the Text/Html, Static Content, Multi-Content, Documents, Links, Media and other modules to create and manage page content. Use page management tools to create and maintain pages, meta-data and permissions.

Host Nucleus with Microsoft Internet Information Services (IIS) on Windows, Azure App Service or Linux. For data storage, Nucleus supports Microsoft SQL Server, Sqlite, MySql, MariaDB and PostgreSQL.

Built in support for role-based permissions, including a user interface to easily manage security roles, role groups, users, user role assignments and API access rights. Site administrators can add or remove custom user profile properties, and control whether users can self-sign up to the site.

Store your files in Local Storage, on a File Server or Storage Area Network (SAN), or use Microsoft Azure Storage or Amazon S3.

Use the OAuth client extension to provide single sign-on from Facebook, Google, Twitter, Microsoft or other OAuth identity providers, or use the SAML client extension to authenticate with your enterprise or cloud-based SAML identity provider.

Our extensible search system automatically indexes your content and provides full-text search.  A simple search provider is built in, and our free Elastic Search Provider extension integrates with Elastic Search.

Use OpenTelemetry metrics (instrumentation) and health checks to monitor your web applications and site.

The free Nucleus Developer Tools consist of Visual Studio Templates, code analyzers, code fix providers and MSBuild scripts for developers of Nucleus extensions. 

Nucleus is open-source and is licensed under the MIT license. Source code is available at GitHub.