DotLiquid by: Tim Jones, Alessandro Petrelli

DotLiquid is a templating system ported to the .NET framework from Ruby’s Liquid Markup.

DotNet.Testcontainers by: Andre Hofmeister and contributors

A lightweight library to run tests with throwaway instances of Docker containers.

Fable by: Alfonso García-Caro Núñez

F# to JS compiler

FastEndpoints by: FastEndpoints

A light-weight REST Api framework for ASP.Net 6 and newer that implements REPR (Request-Endpoint-Response) Pattern.

FastEndpoints.Attributes by: FastEndpoints

Attributes used by FastEndpoints.

FluentAssertions by: Dennis Doomen, Jonas Nyrup, Xceed

A very extensive set of extension methods that allow you to more naturally specify the expected outcome of a TDD or BDD-style unit tests. Works with .NET Standard 2.0 and higher, .NET Framework 4.7 and higher and .NET 6 and higher. Supports the unit test frameworks MSTest2, NUnit3, NUnit4, XUnit2, XUnit3, MSpec and TUnit. IMPORTANT: This version is free for open-source projects and non-commercial use, but commercial use requires [a paid license](https://xceed.com/products/unit-testing/fluent-assertions/). Check out the [license page](LICENSE) for more information.

FluentMigrator.Abstractions by: Sean Chambers, Josh Coffman, Tom Marien, Mark Junker, John Zabroski

FluentMigrator is a database migration framework for .NET written in C#. The basic idea is that you can create migrations which are simply classes that derive from the Migration base class and have a Migration attribute with a unique version number attached to them. Upon executing FluentMigrator, you tell it which version to migrate to and it will run all necessary migrations in order to bring your database up to that version. In addition to forward migration support, FluentMigrator also supports different ways to execute the migrations along with selective migrations called profiles and executing arbitrary SQL.

FluentValidation by: Jeremy Skinner

A validation library for .NET that uses a fluent interface to construct strongly-typed validation rules.

gherkin by: aslakhellesoy

A fast lexer and parser for the Gherkin language based on Ragel

Google.Protobuf by: Google Inc.

C# runtime library for Protocol Buffers - Google's data interchange format.

Grpc by: Google Inc.

C# implementation of gRPC - an RPC library and framework. See project site for more info.

Grpc.AspNetCore.Server by: The gRPC Authors

gRPC support for ASP.NET Core

Grpc.Core.Api by: The gRPC Authors

gRPC C# Surface API

Grpc.Net.ClientFactory by: The gRPC Authors

HttpClientFactory integration the for gRPC .NET client

Grpc.Net.Common by: The gRPC Authors

Infrastructure for common functionality in gRPC

Grpc.Reflection by: The gRPC Authors

gRPC C# Server Reflection

Grpc.Tools by: The gRPC Authors

gRPC and Protocol Buffer compiler for managed C# and native C++ projects. Add this package to a project that contains .proto files to be compiled to code. It contains the compilers, include files and project system integration for gRPC and Protocol buffer service description files necessary to build them on Windows, Linux and MacOS. Managed runtime is supplied separately in the Grpc.Core package.

Handlebars.Net by: Rex Morgan

Blistering-fast Handlebars.js templates in your .NET application.

HarfBuzzSharp by: Microsoft

HarfBuzzSharp is a cross-platform OpenType text shaping engine for .NET platforms.

HtmlAgilityPack by: ZZZ Projects, Simon Mourrier, Jeff Klawiter, Stephan Grell

This is an agile HTML parser that builds a read/write DOM and supports plain XPATH or XSLT (you actually don't HAVE to understand XPATH nor XSLT to use it, don't worry...). It is a .NET code library that allows you to parse "out of the web" HTML files. The parser is very tolerant with "real world" malformed HTML. The object model is very similar to what proposes System.Xml, but for HTML documents (or streams).