Colorful.Console by: Tom Akita Muhammad Rehan Saeed Matt Furden

Style your C# console output!

Castle.Core by: Castle Project Contributors

Castle Project Core, including DynamicProxy, Logging Abstractions and DictionaryAdapter

FluentValidation by: Jeremy Skinner

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

FastMember by: Marc Gravell

In .NET reflection is slow... well, kinda slow. If you need access to the members of an arbitrary type, with the type and member-names known only at runtime - then it is frankly hard (especially for DLR types). This library makes such access easy and fast.

CommonServiceLocator by: .NET Foundation and Contributors

The library provides an abstraction over IoC containers and service locators. Using the library allows an application to indirectly access the capabilities without relying on hard references.

AsyncUsageAnalyzers by: Sam Harwell et. al.

A collection of analyzers related to best practices for writing asynchronous code.

AutoMapper by: Jimmy Bogard

A convention-based object-object mapper. AutoMapper uses a fluent configuration API to define an object-object mapping strategy. AutoMapper uses a convention-based matching algorithm to match up source to destination values. Currently, AutoMapper is geared towards model projection scenarios to flatten complex object models to DTOs and other simple objects, whose design is better suited for serialization, communication, messaging, or simply an anti-corruption layer between the domain and application layer.

ExcelNumberFormat by: ExcelNumberFormat developers

.NET library to parse ECMA-376 number format strings and format values like Excel and other spreadsheet softwares.

DotNetAnalyzers.PublicApiAnalyzer by: Sam Harwell et. al.

An analyzer for packages with public APIs.

Hl7.Fhir.Serialization by: Ewout Kramer (ewout@fire.ly) and contributors

Contains general interfaces and classes for working with FHIR data, regardless of FHIR version or POCO's

CSharpFunctionalExtensions by: Vladimir Khorikov

CSharpFunctionalExtensions - functional extensions for C#.

CsvHelper by: Josh Close

A library for reading and writing CSV files. Extremely fast, flexible, and easy to use. Supports reading and writing of custom class objects.

DocumentFormat.OpenXml by: Microsoft

The Open XML SDK provides tools for working with Office Word, Excel, and PowerPoint documents. It supports scenarios such as: - High-performance generation of word-processing documents, spreadsheets, and presentations. - Populating content in Word files from an XML data source. - Splitting up (shredding) a Word or PowerPoint file into multiple files, and combining multiple Word/PowerPoint files into a single file. - Extraction of data from Excel documents. - Searching and replacing content in Word/PowerPoint using regular expressions. - Updating cached data and embedded spreadsheets for charts in Word/PowerPoint. - Document modification, such as removing tracked revisions or removing unacceptable content from documents.

Flurl by: Todd Menier

A fluent, portable URL builder. To make HTTP calls off the fluent chain, check out Flurl.Http.

Dapper by: Sam Saffron Marc Gravell

A high performance Micro-ORM supporting Sql Server, MySQL, Sqlite, SqlCE, Firebird etc..

EPPlus by: Jan Källman

A library to manage Excel spreadsheets, using OOXML.

DeviceId by: Matthew King

Provides functionality to generate a 'device ID' that can be used to uniquely identify a computer.

Hl7.FhirPath by: Ewout Kramer (ewout@fire.ly) and contributors

This library contains a runtime environment for executing HL7 FhirPath queries and invariants. It is used by the HL7 .NET FHIR API (https://www.nuget.org/packages/Hl7.Fhir.DSTU2) to run validation for the HL7 FHIR object model.

FluentMigrator by: Josh Coffman Tom Marien

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.

DotNetAnalyzers.PublicApiAnalyzer.Unstable by: Sam Harwell et. al.

An analyzer for packages with public APIs.