Command line parsing, invocation, and rendering of terminal output.

The mobile app vault (iOS and Android).

Accept Bitcoin payments. Free, open-source & self-hosted, Bitcoin payment processor.

Open Source Web Application Framework for ASP.NET Core

Highly performant and modular controls for node-based editors designed for data-binding and MVVM.

Google's Material Design in XAML & WPF, for C# & VB.Net.

Build Mobile, Desktop and WebAssembly apps with C# and XAML. Today. Open source and professionally supported.

A cross-platform plotting library for .NET

:cake: Cake (C# Make) is a cross platform build automation system.

.NET for Apache® Spark™ makes Apache Spark™ easily accessible to .NET developers.

xUnit.net is a free, open source, community-focused unit testing tool for the .NET Framework.

.NET core API Gateway

AutoFixture is an open source library for .NET designed to minimize the 'Arrange' phase of your unit tests in order to maximize maintainability. Its primary goal is to allow developers to focus on what is being tested rather than how to setup the test scenario, by making it easier to create object graphs containing test data.

EF Core is a modern object-database mapper for .NET. It supports LINQ queries, change tracking, updates, and schema migrations.

Lean Algorithmic Trading Engine by QuantConnect (Python, C#)

💫 NClient is an automatic type-safe .Net HTTP client that allows you to call web service API methods using annotated interfaces or controllers without boilerplate code.

Linq to database provider.

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

Powerful .NET library for benchmarking

Every programmer needs a rubberduck. COM add-in for the VBA & VB6 IDE (VBE).

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

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

A wrapper executable that can run any executable as a Windows service, in a permissive license.

Mono open source ECMA CLI, C# and .NET implementation.

One framework for creating powerful cross-platform games.

An open source fork of Windows Live Writer

Headless Chrome .NET API