Best Open Source dotnet Libraries

#1jellyfin/jellyfin

The Free Software Media System - Server Backend & API

#2files-community/Files

A modern file manager that helps users organize their files and folders.

#3dotnet/aspnetcore

ASP.NET Core is a cross-platform .NET framework for building modern cloud-based web applications on Windows, Mac, or Linux.

#4SeleniumHQ/selenium

A browser automation framework and ecosystem.

#5AvaloniaUI/Avalonia

Develop Desktop, Embedded, Mobile and WebAssembly apps with C# and XAML. The most popular .NET UI client technology

#6pulumi/pulumi

Pulumi - Infrastructure as Code in any programming language 🚀

#7BeyondDimension/SteamTools

🛠「Watt Toolkit」是一个开源跨平台的多功能 Steam 工具箱。

#8icsharpcode/ILSpy

.NET Decompiler with support for PDB generation, ReadyToRun, Metadata (&more) - cross-platform!

#9jasontaylordev/CleanArchitecture

Clean Architecture Solution Template for ASP.NET Core

#10MoienTajik/AspNetCore-Developer-Roadmap

Roadmap to becoming an ASP.NET Core developer in 2026

#11bitwarden/server

Bitwarden infrastructure/backend (API, database, Docker, etc).

#12ardalis/CleanArchitecture

Clean Architecture Solution Template: A proven Clean Architecture Template for ASP.NET Core 10

#13dotnet/runtime

.NET is a cross-platform runtime for cloud, mobile, desktop, and IoT apps.

#14microsoft/react-native-windows

A framework for building native Windows apps with React.

#15OpenRA/OpenRA

Open Source real-time strategy game engine for early Westwood games such as Command & Conquer: Red Alert written in C# using SDL and OpenGL. Runs on Windows, Linux, *BSD and Mac OS X.

#16amplication/amplication

Amplication brings order to the chaos of large-scale software development by creating Golden Paths for developers - streamlined workflows that drive consistency, enable high-quality code practices, simplify onboarding, and accelerate standardized delivery across teams.

#17unoplatform/uno

Open-source platform for building cross-platform native Mobile, Web, Desktop and Embedded apps quickly. Create rich, C#/XAML, single-codebase apps from any IDE. Hot Reload included! 90m+ NuGet Downloads!!

#18studyzy/imewlconverter

”深蓝词库转换“ 一款开源免费的输入法词库转换程序

#19egametang/ET

Unity3D Client And C# Server Framework

#20bchavez/Bogus

:card_index: A simple fake data generator for C#, F#, and VB.NET. Based on and ported from the famed faker.js.

#21microsoft/agent-framework

A framework for building, orchestrating and deploying AI agents and multi-agent workflows with support for Python and .NET.

#22reactiveui/refit

The automatic type-safe REST library for .NET Core, Xamarin and .NET. Heavily inspired by Square's Retrofit library, Refit turns your REST API into a live interface.

#23litedb-org/LiteDB

LiteDB - A .NET NoSQL Document Store in a single data file

#24dotnet/machinelearning

ML.NET is an open source and cross-platform machine learning framework for .NET.

#25lepoco/wpfui

WPF UI provides the Fluent experience in your known and loved WPF framework. Intuitive design, themes, navigation and new immersive controls. All natively and effortlessly.

#26ThreeMammals/Ocelot

.NET API Gateway

#27microsoft/aspire

Aspire is the tool for code-first, extensible, observable dev and deploy.

#28Tyrrrz/CliWrap

Library for interacting with command-line interfaces

#29mpvnet-player/mpv.net

🎞 mpv.net is a media player for Windows with a modern GUI.

#30commandlineparser/commandline

The best C# command line parser that brings standardized *nix getopt style, for .NET. Includes F# support

#31apache/avro

Apache Avro is a data serialization system.

#32zeromq/netmq

A 100% native C# implementation of ZeroMQ for .NET

#33monksoul/Furion

让 .NET 开发更简单，更通用，更流行。

#34meziantou/Meziantou.Framework

#35getsentry/sentry-dotnet

Sentry SDK for .NET

#36open-telemetry/opentelemetry-dotnet-contrib

This repository contains set of components extending functionality of the OpenTelemetry .NET SDK. Instrumentation libraries, exporters, and other components can find their home here.

#37OpenAiTx/OpenAiTx

Auto-translate platform for your GitHub project readme & wiki.

#38LumiBearStudio/SpanFinder

macOS Finder-style Miller Columns file explorer for Windows — multi-tab, split view, 10 themes, keyboard-first, FTP/SFTP

#39Aiko-IT-Systems/DisCatSharp

Your library to write discord apps in C# with focus on always providing access to the latest discord features