* [Boo](https://github.com/bamboo/boo) - A .NET language similar to Python but with static typing, and many meta-programming capabilities.

* [Dynamic Language Runtime](http://www.github.com/IronLanguages/main) - A toolkit for building dynamic languages for .NET.

* [Eagle](https://eagle.to) - A .NET implementation of the [Tcl](https://www.tcl.tk) programming language, built on the CLR.

* [Essence#](https://github.com/EssenceSharp/cSharp) - Essence# is a fully dynamic and highly polymorphic programming language which features pervasive message passing, pervasive dynamic and strong typing, pervasive and deep reflection and pervasive object orientation.

* [Lucene.Net](https://github.com/apache/lucene.net) - A .NET full-text search engine framework that is a C# port of the popular Apache Lucene project.

* [MahApps.Metro.IconPacks](https://github.com/MahApps/MahApps.Metro.IconPacks) - Some awesome icons for `WPF` and `UWP` all together. The library contains controls to use icons from [Material Design](https://materialdesignicons.com/), [Material Design Icons Light](https://github.com/Templarian/MaterialDesignLight), [Font Awesome](http://fontawesome.io/icons/), [GitHub Octicons](https://octicons.github.com/), [Modern](http://modernuiicons.com/), [Entypo+](http://www.entypo.com/) and [Simple Icons](https://simpleicons.org/).

* [Math.NET Numerics](https://github.com/mathnet/mathnet-numerics) - Provides methods and algorithms for numerical computations in science, engineering and every day use.

* [Mathos Parser](https://github.com/MathosProject/Mathos-Project) - A simple parser for mathematical expressions before and at runtime.

* [Mjolnir](https://github.com/hudl/Mjolnir) - [Hystrix](https://github.com/Netflix/Hystrix)-inspired fault tolerance with circuit breakers and thread pools.

* [MoreLINQ](https://morelinq.github.io/) - LINQ to Objects is missing a few desirable features. This project will enhance LINQ to Objects with extra methods, in a manner which keeps to the spirit of LINQ.

* [NAudio](https://github.com/naudio/NAudio) - An open source .NET audio and MIDI library.

* [NEST](https://github.com/elastic/elasticsearch-net) - The official .NET client library for Elasticsearch.

* [NetTopologySuite](https://github.com/NetTopologySuite) - A .NET port of the JTS Topology Suite.

* [NModbus4](https://github.com/NModbus4/NModbus4) - Implementation of the Modbus protocol.

* [NodaTime](https://nodatime.org/) - A better date and time API for .NET.

* [NPOI](https://github.com/tonyqus/npoi) - An Office file formats (xls, xlsx, docx) read/write library for .NET.

* [Cake](https://github.com/cake-build/cake) (C# Make) - A build automation system with C#/Roslyn driven build scripts.

* [CInject](https://github.com/punitganshani/CodeInject) - A tool to inject your C#/VB.NET code into existing .NET assemblies and executables

* [CppSharp](https://github.com/mono/CppSharp) - C/C++ bindings generation for .NET.

* [dnSpy](https://github.com/0xd4d/dnSpy) - A .NET decompiler, debugger, and assembly editor that lets you edit and debug assemblies even if you don't have their source code.

* [FAKE](http://fsharp.github.io/FAKE/) - Build automation system with capabilities which are similar to make and rake.

* [FlubuCore](https://github.com/flubu-core/flubu.core) - A cross platform build and deployment automation system for building projects and executing deployment scripts using C# code.

* [Autofac](https://github.com/autofac/Autofac) - Autofac is an addictive Inversion of Control container for .NET 4.5, Silverlight 5, Windows Store apps, and Windows Phone 8 apps.

* [Castle Windsor](https://github.com/castleproject/Windsor) - A mature Inversion of Control container available for .NET and Silverlight

* [dI.Hook](https://github.com/punitganshani/dI.Hook) - DI container that allows invocation using AOP

* [DryIoc](https://bitbucket.org/dadhi/dryioc) - DryIoc is small, fast, capable IoC Container for .NET

* [fFastInjector](https://github.com/Grax32/fFastInjector/) - fFastInjector is a high-performing dependency injector, service locator, and/or IOC (inversion of control) container.

* [Funq](https://funq.codeplex.com/) - A fast DI container you can understand. (No Recent Updates - Still on CodePlex - 4/2018)

* [Grace](https://github.com/ipjohnson/Grace) - Grace is a feature rich Dependency Injection container in a portable class library

* [Griffin](https://github.com/jgauffin/griffin.container) - Inversion of control container with (almost) zero configuration

* [Hiro](https://github.com/philiplaureano/Hiro) - An ultra-lightweight, inversion of control container compiler framework

* [IfInjector](https://github.com/iamahern/IfInjector) - High performance mobile micro-IoC container.

* [LightCore](https://peterbucher.kilnhg.com/Code/LightCore/Group/Default?nr=) - [A lightweight dependency injection container](http://lightcore.ch/en/default.aspx) that can be used as a service locator and despite its simplicity and ease boasts numerous features.