Browse free open source C# Frameworks and projects below. Use the toggles on the left to filter open source C# Frameworks by OS, license, language, programming language, and project status.

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    MongoDB Atlas runs apps anywhere

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  • 1
    Service Bus is planned to be a multiplatform comunication bus, foscused on secured comunications
    Downloads: 0 This Week
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  • 2
    The Service Invocation Framework ( SIF ) is a framework for stream lining the creation & deployment of .NET Windows Services. It contains all of the plumbing and base classes required to create a windows service from scratch.
    Downloads: 0 This Week
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  • 3
    ServiceStack

    ServiceStack

    Simple, fast, versatile and full-featured services framework

    One framework to power them all. Write your HTTP APIs once and take advantage of end-to-end typed integrations for all popular web, mobile and desktop platforms. ServiceStack's primary goal is to enhance the value of System APIs which serve as the blueprint that most features centered around. By using simple & pure dependency-free DTO models decoupled from any implementation we're free to continue layering on features which now sees ServiceStack APIs as the most versatile in the world where the same high-performance APIs can be consumed from HTTP in any combination of Route, QueryString, FormData or a myriad of data formats, via popular resilient MQ Servers whilst simultaneously supporting legacy integrations like SOAP or adopting new technologies like gRPC without sacrificing any native HTTP integrations. To maximize the value of APIs we're focused beyond the API boundary by making it as simple as possible for API Consumers to call your APIs.
    Downloads: 0 This Week
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  • 4
    A Tool for generating C# code and T-SQL stored procedures for use in database-centric, layered enterprise application development. Also includes basic a SQL Querying engine and a duplicate record remover!
    Downloads: 0 This Week
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  • Ship Agents Faster Icon
    Ship Agents Faster

    Transform your applications and workflows into powerful agentic systems at global scale.

    Gemini Enterprise Agent Platform lets you rapidly build, scale, govern and optimize production-ready agents grounded in your organization's data. The platform enables developers to build custom or pre-built agents for virtually any use case. New customers get $300 in free credits.
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  • 5
    Sharp2p helps you including peer-to-peer functionalities in your .NET software. It is written in C# and lets you implement new p2p networks or use well known (CAN, Pastry, etc..)
    Downloads: 0 This Week
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  • 6
    SharpAssembler
    This library assembles machine instructions (e.g. x86-64) represented as managed .NET objects. It provides an intuitive object model that can be manipulated and emitted to various object file formats (e.g. bin, elf) from C# and other .NET languages.
    Downloads: 0 This Week
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  • 7
    A light-weight component model and services framework providing enterprise quality services.
    Downloads: 0 This Week
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  • 8
    SharpScraps is a collection of C# framework wrappers, including code to facilitate diagnostics, HTML parsing, and screen capturing (among other things).
    Downloads: 0 This Week
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  • 9
    Development is continued under the regular sharptiles project. See http://www.sharptiles.org
    Downloads: 0 This Week
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  • 10
    ShowX is a .NET set of libraries aimed to provide automatical representation of classes over Web or Windows application, by using controls to automate operations over those class intances
    Downloads: 0 This Week
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  • 11
    SignalR

    SignalR

    Incredibly simple real-time web for .NET

    Today's modern apps are expected to deliver up-to-date information without hitting a refresh button. Add real-time functionality to your dashboards, maps, games and more. What is real-time functionality? It's the ability to have your server-side code push content to connected clients as it happens, in real-time. SignalR hubs can be written in C# code and added to your ASP.NET app, alongside your pages and APIs. The simple programming model integrates seamlessly with other ASP.NET features like dependency injection, authentication, authorization, and scalability. While chat is often used as an example, you can do a whole lot more. Any time a user refreshes a web page to see new data, or the page implements Ajax long polling to retrieve new data, it's candidate for using SignalR. SignalR also enables completely new types of applications that require high-frequency updates from the server, such as real-time gaming.
    Downloads: 0 This Week
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  • 12
    This project is intended to provide an easy way for developers to have XAPs downloaded dynamically at runtime. A simple interface needs to be implimented and then XAPs can be downloaded on demand, or ahead of demand.
    Downloads: 0 This Week
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  • 13
    A silverlight sandbox framework.
    Downloads: 0 This Week
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  • 14
    Silverlight designer is a Easy and Visual designer for Microsoft Silverlight.
    Downloads: 0 This Week
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  • 15
    This project provides a framework upon which a Silverlight user interface can be created. It provides control navigation, pop-up windows, data-bound controls, and some basic user controls. The framework is XAML-driven and coded in C#.
    Downloads: 0 This Week
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  • 16
    Simios is a collection of libraries and tools to ease development on any CLI framwork, focusing in mono and MS.NET. All libraries are 100% managed and are beeing developed by the Simios.org community with some support by other Mono communities as well.
    Downloads: 0 This Week
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  • 17

    SimplGraphics

    provides simple geometry oriented graphics based on gdi+

    basic gdi+ graphics and geometric shapes to paint on a WinForm. optimized for special form paint appliances.
    Downloads: 0 This Week
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  • 18
    A light-weight C#.Net library to manage storage and retrieval of user settings. The actual data storage is configurable and adapters for standard Sql databases including SQLite, XML files, and flat files are planned.
    Downloads: 0 This Week
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  • 19
    SimpleValidation is an easy validation framework for Microsoft .NET applications. Validation information is stored in an XML file and fields are validated for an object passed in using a set of field information and rules.
    Downloads: 0 This Week
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  • 20
    Sinergia is web based framework for developing help desk solutions in C#, NET 3.5. Customization is supported at the data structure and business process levels with workflow foundation.
    Downloads: 0 This Week
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  • 21
    Sisk Framework

    Sisk Framework

    Sisk's request and response processor mainframe source code

    Sisk is a lightweight web framework designed for fast and robust development, which allows you to take the full control of what you want to do. Sisk allows you to create quick or large projects with as little code as possible, quickly, focused on enabling development your way. Sisk enables web development the way you want. Create MVC, MVVM, SOLID applications, or any other design pattern you're interested in. Robust projects tested in small, low-cost, low-performance environments with good, stable results. The entire Sisk ecosystem is less than 500 KB in size. The entire Sisk ecosystem is open source, and all the libraries and technologies we use are also open source. Sisk is entirely distributed under the MIT License, which allows commercial development. You are the one who makes the project, Sisk gives you the tools. Because it is open source, the community (including you) can maintain, fix bugs, and improve Sisk over time.
    Downloads: 0 This Week
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  • 22
    Smart Thread Pool is a rich thread pool implemented in pure .net and can run on Windows, WindowsCE, Silverlight, ASP.NET, and Mono.
    Downloads: 0 This Week
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  • 23
    SmartCache is a cache project which provides storage facility for temporay objects in memory and disc. Main usage is in the smartclient to store temporary objects on the client side. It deals both static and non static nature of data.
    Downloads: 0 This Week
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  • 24
    SmartEnum

    SmartEnum

    A base class for creating strongly typed enum replacements in C#

    SmartEnum is a .NET library that provides a strongly typed alternative to traditional C# enums by allowing developers to create richer, object-oriented enumeration classes. Instead of being limited to primitive numeric values, SmartEnum enables enums to include behavior, validation, and additional properties while preserving type safety and readability. The library is widely used in domain-driven design scenarios where business concepts require more expressive modeling than standard enums allow. Developers define custom enumerations by inheriting from a base SmartEnum class and declaring static instances, which can then be queried by name or value. The project also includes ecosystem support for serialization, Entity Framework persistence, and validation attributes, making it suitable for real-world enterprise applications. Overall, SmartEnum helps teams write more maintainable and intention-revealing domain code by replacing brittle primitive enums with extensible types.
    Downloads: 0 This Week
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  • 25
    Smartstore

    Smartstore

    Open Source ASP.NET MVC Enterprise eCommerce Shopping Cart Solution

    Smartstore is a free, open-source, full-featured e-commerce solution for companies of any size. It is web standards compliant and incorporates the newest Microsoft web technology stack. Smartstore includes all essential features to create multilingual and multi-currency stores targeting desktop or mobile devices and enabling SEO optimized rich product catalogs with support for an unlimited number of products and categories, variants, bundles, datasheets, ESD, discounts, coupons and many more. A comprehensive set of tools for CRM & CMS, sales, marketing, payment & shipping handling, etc. makes Smartstore a powerful all-in-one solution fulfilling all your needs. State of the art architecture thanks to ASP.NET 4.5, ASP.NET MVC 5, Entity Framework 6 and Domain Driven Design. Easy to extend and extremely flexible thanks to modular design. Highly scalable thanks to full page caching and web farm support.
    Downloads: 0 This Week
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