protobuf-net.Core by: Marc Gravell

Provides simple access to fast and efficient "Protocol Buffers" serialization from .NET applications

PuppeteerSharp by: Darío Kondratiuk

Headless Browser .NET API

QRCoder by: Raffael Herrmann

QRCoder is a simple library, written in C#.NET, which enables you to create QR codes.

QRCoder.Core by: Afonso Dutra Nogueira Filho

QRCoder.Core, written in C#.NET, which enables you to create QR codes Use System.Drawing.Common below 7.0.0.

QRCoder-ImageSharp by: Raffael Herrmann Joerg Plenert

QRCoder is a simple library, written in C#.NET, which enables you to create QR codes. Based on ImageSharp to provide plattform independency.

Quartz by: Marko Lahma Quartz.NET

Quartz Scheduling Framework for .NET

Quartz.Extensions.DependencyInjection by: Facundo Glaeser Marko Lahma Quartz.NET

Quartz.NET Microsoft.Extensions.DependencyInjection integration; Quartz Scheduling Framework for .NET

Quartz.Extensions.Hosting by: Andrew Lock Marko Lahma Quartz.NET

Quartz.NET Generic Host integration; Quartz Scheduling Framework for .NET

Quartz.Serialization.Json by: Marko Lahma Quartz.NET

Quartz.NET JSON Serialization Support; Quartz Scheduling Framework for .NET

QueryDesigner by: Vladislav Zhukov

QueryDesigner provides way of creating complex IQueryable filtering based on dynamic expression trees.

QuestPDF by: MarcinZiabek

Generate and edit PDF documents in your .NET applications using the open-source QuestPDF library and its C# Fluent API. Build invoices, reports and data exports with ease.

Quill.Delta by: blushingpenguin nozer

Converts Quill's Delta format to HTML/XHTML

RabbitMQ.Client by: Broadcom

The RabbitMQ .NET client is the official client library for C# (and, implicitly, other .NET languages)

Rafty by: Tom Pallister

RAFT consensus implementation

RavenDB.Client by: Hibernating Rhinos

RavenDB Client is the client library for accessing RavenDB

RBush by: viceroypenguin

Spatial Index data structure; used to make it easier to find data points on a two dimensional plane.

RBush.Signed by: viceroypenguin

Spatial Index data structure; used to make it easier to find data points on a two dimensional plane.

realtime-csharp by: Joseph Schultz <joseph@acupofjose.com>

Realtime-csharp is written as a client library for supabase/realtime.

ReflectionBridge by: Stef Heyenrath

Provides some extensions which define a bridge for the differences between Type and TypeInfo.

Refractored.MvvmHelpers by: James Montemagno

Collection of MVVM Helpers such as ObservableRangeCollection, BaseViewModel, Grouping, and others.