DocumentFormat.OpenXml by: Microsoft

Official NuGet for DocumentFormat.OpenXml

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.

EPPlus by: EPPlus Software AB

A spreadsheet library for .NET framework and .NET core

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.

FluentAssertions by: Dennis Doomen, Jonas Nyrup

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. Targets .NET Framework 4.5 and 4.7, as well as .NET Core 2.0, .NET Core 3.0, .NET Core 2.1, .NET Standard 1.3, 1.6, 2.0 and 2.1. Supports the unit test frameworks MSTest, MSTest2, Gallio, NUnit, XUnit, MBUnit, MSpec, and NSpec.

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.AspNetCore.Server by: The gRPC Authors

gRPC support for ASP.NET Core

Grpc.AspNetCore.Server.ClientFactory by: The gRPC Authors

HttpClientFactory integration the for gRPC .NET client when running in ASP.NET Core

Grpc.Core by: The gRPC Authors

C# implementation of gRPC based on native gRPC C-core library. Note that the Grpc.Core implementation of gRPC for C# is in maintenance mode and will be replaced by grpc-dotnet in the future. See https://grpc.io/blog/grpc-csharp-future/ for details.

Grpc.Core.Api by: The gRPC Authors

gRPC C# Surface API

Grpc.Net.Client by: The gRPC Authors

.NET client for gRPC

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.Tools by: The gRPC Authors

gRPC and Protocol Buffer compiler for C# projects

Handlebars.Net by: Rex Morgan

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

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).