Open Source C# Frameworks
Sort By:
C# Frameworks
View 166 business solutionsBrowse 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.
-
Build Agents and Models on One PlatformGemini Enterprise Agent Platform is Google Cloud's comprehensive platform for developers to build, scale, govern, and optimize agents and models. Choose from Google's most advanced models and third-party models like Anthropic's Claude Model Family.
-
$300 Free Credits to Build on Google CloudPut your $300 in credit toward real workloads, then keep building with free monthly usage for 20+ products. No commitment and no charge until you upgrade.
-
1
BepInEx
Unity / XNA game patcher and plugin framework
Unity / XNA game patcher and plugin framework. BepInEx is a plugin / modding framework for Unity Mono, IL2CPP, and .NET framework games (XNA, FNA, MonoGame, etc.) Stable builds are released once a new iteration of BepInEx is considered feature-complete. They have the least bugs, but some newest features might not be available. Bleeding edge builds are available on BepisBuilds. Bleeding edge builds are always the latest builds of the source code. Thus they are the opposite to stable builds: they have the newest features and bugfixes available, but usually tend to be the most buggy. Therefore you should use bleeding edge builds only if you are asked to or if you want to preview the upcoming version of BepInEx. Some games require some additional changes in order to work around specific limitations of different Unity versions. -
2
PowerShell
Command-line shell and scripting language built on .NET
Powershell is a cross-platform, task-based command-line shell and scripting language that helps rapidly automate tasks that manage operating systems (Linux, macOS and Windows) and processes. It works well with existing tools and is optimized for dealing with structured data, REST APIs and object models. PowerShell was developed by Microsoft as a task management and configuration management framework. Powershell is designed to let you manage computers from the command line and improve the command-line and scripting environment. -
3
mpv.net
mpv.net is a modern media player for Windows that works just like mpv
mpv.net is a modern desktop media player for Windows based on the popular mpv player. mpv.net is designed to be mpv compatible, almost all mpv features are available because they are all contained in libmpv, this means the official mpv manual applies to mpv.net. mpv focuses on the usage of the command line and the terminal, mpv.net retains the ability to be used from the command line and the terminal and adds a modern Windows GUI on top of it. Video output that is capable of many features loved by videophiles, such as video scaling with popular high-quality algorithms, color management, frame timing, interpolation, HDR, and more. Leverages the FFmpeg hwaccel APIs to support DXVA2 video decoding acceleration. mpv.net is based on libmpv which offers a straightforward C API that was designed from the ground up to make mpv usable as a library and facilitate easy integration into other applications. mpv is like VLC not based on DirectShow or Media Foundation. -
4
Selenium
Browser automation framework and ecosystem
Selenium automates browsers. That's it! What you do with that power is entirely up to you. Primarily it is for automating web applications for testing purposes, but is certainly not limited to just that. Boring web-based administration tasks can (and should) also be automated as well. If you want to create robust, browser-based regression automation suites and tests, scale and distribute scripts across many environments, then you want to use Selenium WebDriver, a collection of language specific bindings to drive a browser - the way it is meant to be driven. If you want to create quick bug reproduction scripts, create scripts to aid in automation-aided exploratory testing, then you want to use Selenium IDE; a Chrome and Firefox add-on that will do simple record-and-playback of interactions with the browser. If you want to scale by distributing and running tests on several machines and manage multiple environments from a central point. -
Custom VMs From 1 to 96 vCPUs With 99.95% UptimeLive migration and automatic failover keep workloads online through maintenance. One free e2-micro VM every month.
-
5
Grassroots DICOM
Cross-platform DICOM implementation
Grassroots DiCoM is a C++ library for DICOM medical files. It is accessible from Python, C#, Java and PHP. It supports RAW, JPEG, JPEG 2000, JPEG-LS, RLE and deflated transfer syntax. It comes with a super fast scanner implementation to quickly scan hundreds of DICOM files. It supports SCU network operations (C-ECHO, C-FIND, C-STORE, C-MOVE). PS 3.3 & 3.6 are distributed as XML files. It also provides PS 3.15 certificates and password based mecanism to anonymize and de-identify DICOM datasets. -
6
.NET Runtime
Cross-platform runtime for cloud, mobile, desktop, and IoT apps
.NET is a free, cross-platform, open source developer platform for building many different types of applications. With .NET, you can use multiple languages, editors, and libraries to build for web, mobile, desktop, games, and IoT. You can write .NET apps in C#, F#, or Visual Basic. C# is a simple, modern, object-oriented, and type-safe programming language. F# is a cross-platform, open-source, functional programming language for .NET. It also includes object-oriented and imperative programming. Visual Basic is an approachable language with a simple syntax for building type-safe, object-oriented apps. Whether you're working in C#, F#, or Visual Basic, your code will run natively on any compatible OS. Different .NET implementations handle the heavy lifting for you. -
7
StabilityMatrix
Multi-Platform Package Manager for Stable Diffusion
StabilityMatrix is a project that helps organize, evaluate, and compare generative AI models and their behavior across prompts, datasets, or configuration settings. It provides a framework to run experiments systematically—capturing inputs, model configurations, outputs, and metrics—so researchers and practitioners can reason about differences in quality, robustness, and failure modes. The repository often bundles tooling for automated prompt sweeping, scoring heuristics (such as diversity, coherence, or task-specific metrics), and visualization helpers to make comparisons interpretable. This approach is useful for model selection, prompt engineering, and benchmarking new checkpoints against baseline models under reproducible conditions. By turning ad-hoc tests into tracked experiments, StabilityMatrix reduces bias, surfaces subtle regressions, and accelerates iteration when tuning generative systems. -
8
CefSharp
.NET bindings for the Chromium embedded framework
CefSharp is an easy way to embed a full-featured standards-compliant web browser into your C# or VB.NET app. CefSharp has browser controls for WinForms and WPF apps, and a headless (offscreen) version for automation projects too. CefSharp is based on Chromium Embedded Framework, the open source version of Google Chrome. CefSharp embraces modern web standards, and supports HTML5, JavaScript, CSS3 and HTML5 audio/video elements. 3D content is supported via WebGL which uses OpenGL/DirectX for hardware accelerated rendering. CefSharp includes embedded modules for PDF, web page printing and the WebKit Inspector (developer tools). CefSharp has no external dependencies, and the full build of CefSharp only adds ~80 MB to your app. See the CefSharp.MinimalExample project for ready-to-compile minimal example apps built with CefSharp. Within the projects source there are more complicated example projects. -
9
dotnet sdk
Core functionality needed to create .NET Core projects
Core functionality needed to create .NET Core projects, that is shared between Visual Studio and CLI. There are no fees or licensing costs, including for commercial use. .NET is open-source and cross-platform, with free development tools for Windows, Linux, and macOS. .NET is supported by Microsoft. Microsoft ships official releases that are built and tested on Microsoft-maintained servers in Azure and supported just like any Microsoft product. .NET is open source and we are very thankful for the many contributions it receives from the community. To test your locally built SDK, run eng\dogfood.cmd after building. That script starts a new Powershell with the environment configured to redirect SDK resolution to your build. -
Go from Code to Production URL in SecondsSkip the Kubernetes configs. Cloud Run handles HTTPS, scaling, and infrastructure automatically. Two million requests free per month.
-
10
Json.NET
A popular high-performance JSON framework for .NET
Serialize and deserialize any .NET object with Json.NET's powerful JSON serializer. Create, parse, query and modify JSON using Json.NET's JObject, JArray and JValue objects. Query JSON with an XPath-like syntax. 50% faster than DataContractJsonSerializer, and 250% faster than JavaScriptSerializer. Json.NET makes the simple easy and the complex possible. If you need it, Json.NET supports converting between XML and JSON. Json.NET is open source software and is completely free for commercial use. Json.NET supports Windows, MacOS, Linux, Mono, and Xamarin. Over 1 billion downloads and counting, Json.NET is the number one library on NuGet. Json.NET documentation is the first place to go for help. It includes over 100 code samples. Json.NET is open source under the MIT license and is free for commercial use. -
11
reko
Reko is a binary decompiler
Reko (Swedish: "decent, obliging") is a decompiler for machine code binaries. This project is freely available under the GNU General Public License. The project consists of front ends, core decompiler engine, and back ends to help it achieve its goals. A command line, a Windows GUI, and a ASP.NET front end exist at the time of writing. The decompiler engine receives inputs from the front ends in the form of either individual executable files or decompiler project files. Reko project files contain additional information about a binary file, helpful to the decompilation process or for formatting the output. The decompiler engine then proceeds to analyze the input binary. Reko has the ambition of supporting decompilation of various processor architectures and executable file formats with minimal user intervention. For a complete list, see the supported binaries page. -
12
Pixeval
Wow. Yet another Pixiv client!
Pixeval is a third-party proxy-free P station client developed by me as an amateur. The UI is implemented using Windows Presentation Foundation , based on .NET Core 3.0 , and supports Windows 7-10 (planning to cancel support other than Win10), and implements most of the The browsing function and many enhancements have been made. It has been open sourced on Github based on the AGPL protocol . The project was conceived in 2018. At that time, the api of the P station was written in Java. At that time, it could also be accessed by modifying the hosts method. After that, GFW The blocking strategy was upgraded, and DNS pollution was upgraded to SNI blocking, so I went to find information to understand the different blocking levels and blocking mechanisms of GFW. I started writing this project in the second half of 2019, which took about 3 months. (Actually, the realization of this project is partly inspired by Notsfsssf. -
13
Obfuscar
Open source obfuscation tool for .NET assemblies
Obfuscar is an open-source .NET obfuscator released under MIT license. It provides basic obfuscation features that help secure secrets in a .NET assembly. An obfuscation tool designed for most .NET developers. Hide everything private, while keep everything public. You can achieve such simply via default settings. Hide class/method/property/event names that you don't want to expose. This is irreversible. String contents can be compressed so that end users won't easily learn them. However, this is reversible by certain tools. -
14
Emgu CV
Emgu CV is a cross platform .Net wrapper for OpenCV
Emgu CV is a cross platform .Net wrapper to the OpenCV image processing library. Allowing OpenCV functions to be called from .NET compatible languages such as C#, VB, VC++, IronPython etc. The wrapper can be compiled in Mono and run on Windows, Linux, Mac OS X, iPhone, iPad and Android devices. -
15
MahApps.Metro
Cobble together a better UI for their own WPF applications
MahApps.Metro is a framework that allows developers to cobble together a Metro or Modern UI for their own WPF applications with minimal effort. MahApps.Metro overrides the default style of all common WPF controls and gives them a modern look. MahApps.Metro also includes some custom controls based on concepts from Windows Phone, Windows 8 and Window 10 (UWP) Apps. You can install MahApps.Metro via the NuGet UI or with the Package Manager Console. If you want to use a pre-release packages of MahApps.Metro, you need to enable Include Prerelease in the NuGet UI. All resources of MahApp.Metro are located within separate resource dictionaries. To adopt the MahApps.Metro theme, you will need to add the resource dictionaries to your App.xaml. To start with the full MahApps styling and full window support you need to change your normal Window to our MetroWindow. -
16
Accord.NET Framework
Machine learning, computer vision, statistics and computing for .NET
The Accord.NET Framework is a .NET machine learning framework combined with audio and image processing libraries completely written in C#. It is a complete framework for building production-grade computer vision, computer audition, signal processing and statistics applications even for commercial use. A comprehensive set of sample applications provide a fast start to get up and running quickly, and extensive documentation and a wiki help fill in the details. The Accord.NET project provides machine learning, statistics, artificial intelligence, computer vision and image processing methods to .NET. It can be used on Microsoft Windows, Xamarin, Unity3D, Windows Store applications, Linux or mobile. After merging with the AForge.NET project, the framework now offers a unified API for learning/training machine learning models that is both easy to use and extensible. -
17
Avalonia
A cross-platform UI framework for .NET
Avalonia is a cross-platform UI framework for dotnet, providing a flexible styling system and supporting a wide range of Operating Systems such as Windows, Linux, macOS. Avalonia is mature and production-ready. We also have in beta release support for iOS, Android and in early stages support for browsers via WASM. Avalonia is open source, free to use, and always will be. Clone the source today to dig deeper. The free VS extension provides everything needed to start, including a XAML previewer. JetBrains deep understanding of Avalonia shines through with rich Rider and R# support. Deploy to the platforms you care about with ease. Leverage existing knowledge, code and packages to kickstart your project. Get the support your project needs with one of our commercial support agreements. Help you can count on. JetBrains delivers huge productivity gains for Avalonia developers. -
18
reacTIVision is a computer vision framework for the fast and robust tracking of markers attached on physical objects, and the creation of multi-touch surfaces. It was designed for the rapid development of table-based tangible user interfaces.
-
19
YAF.NET
YAF.NET - C# ASP.NET Forum
We're focused on fostering community. That's why YAF.NET is open-source, freely available and is supported by people in most parts of the globe. Stable, fast, and mature, YAF.NET has advanced features to empower you and your community. YAF.NET has been around since 2003. During that time, the application has been thoroughly tested. Since the code has been freely available for 9 years, there is nothing to hide and no stone has been left unturned. YAF.NET performance is top-notch. Most long queries are cached. Even for forums with a large number of users and posts, YAF.NET can handle the job quickly with modest hosting requirements. YAF.NET forum is an embeddable (ascx) user-control and supports ASP.NET Membership making integration into DNN and custom solutions possible. YAF.NET is used throughout the globe. YAF.NET supports right-to-left layouts and includes 24 localization. There's also a built-in localization editor to easily make changes to any localization. -
20
taskt
Free and open-source robotic process automation (rpa)
taskt (formerly sharpRPA) is the first truly free, easy-to-use, and open-source process automation client built on the .NET Framework in C#. taskt allows you to build and design process automation without needing to write application code. taskt allows you to automate the boring stuff and create efficienies by giving you the power to craft a digital workforce that executes and performs rule-based automation. No API? No Problem! Included is a "what you see is what you get" bot designer with dozens of automation commands. An element recorder and screen recorder is also included that can record and replay scripted automation. taskt works by allowing a bot developer to design a bot configuration known as a script. The bot configuration is then intepreted by a script engine at run-time and executes against the bot developer's selected parameter inputs. Each command contains the definitions for the required inputs as well as the required logic at run-time. -
21
JPPF
The open source grid computing solution
JPPF makes it easy to parallelize computationally intensive tasks and execute them on a Grid. -
22
.NET port of the excellent Java Hibernate which provides Object/Relational mapping to persist objects in a relational database.
-
23
Windows Presentation Foundation (WPF)
Framework for building Windows desktop applications
Windows Presentation Foundation (WPF) is a UI framework for building Windows desktop applications. WPF supports a broad set of application development features, including an application model, resources, controls, graphics, layout, data binding and documents. WPF uses the Extensible Application Markup Language (XAML) to provide a declarative model for application programming. WPF applications are based on a vector graphics architecture. This enables applications to look great on high DPI monitors, as they can be infinitely scaled. WPF also includes a flexible hosting model, which makes it straightforward to host a video in a button, for example. The visual designer provided in Visual Studio makes it easy to build WPF application, with drag-in-drop and/or direct editing of XAML markup. WinForms is another UI framework for building Windows desktop applications that is supported on .NET (6.0.x/5.0.x/3.1.x). WPF and WinForms applications only run on Windows. -
24
IKVM.NET is a JVM for the Microsoft .NET Framework and Mono. It can both dynamically run Java classes and can be used to convert Java jars into .NET assemblies. It also includes a port of the OpenJDK class libraries to .NET.
-
25
STD Foundation Classes
Object oriented frameworks - PowerBuilder, PowerServer & InfoMaker!
by Chris Pollach (http://chrispollach.blogspot.ca) A fully integrated "object oriented" set of PB Classes for the following products: PowerBuilder, PowerClient & PowerServer. The framework greatly enhances the development process by making the PowerBuilder developer significantly more productive! License: https://sourceforge.net/projects/stdfndclass/files/License (Open Source) => Updated version of the STD "Integrated" framework 2026R1 build 2026.1.0.467 was released to production on 2026-01-09. https://sourceforge.net/projects/stdfndclass/files/FrameWork/Integrated => The STD Framework "Example Apps" 2026 R1 latest builds https://chrispollach.blogspot.com/2026/03/updated.html => Updated version of the STD "Order Entry" example App 2025R2 build 2026.1.0.647 was released on 2026-04-08. https://sourceforge.net/projects/stdfndclass/files/Applications/PowerBuilder/OrderEntry
