Top 20 NuGet attributes Packages

AngleSharp is the ultimate angle brackets parser library. It parses HTML5, CSS3, and XML to construct a DOM based on the official W3C specification.
Creates and inject attributes and properties to existing types in runtime
You can use attributes in the JetBrains.Annotations namespace to annotate your own code to make ReSharper analyze it with greater accuracy and insight.
Route messages based on Routing Attributes. Includes attributes for Exchange, Queue and Routing.
Attribute based mapping for NHibernate.
Contains various basic file functions, functions for working with streams and working with CSV's.
MrAdvice allows to weave aspects at build-time (just like PostSharp, but free as in free beer). Write your own aspects in the form of attributes and apply them to target methods or properties. This version does not require any dependency (on the opposite of MrAdvice.Fody which requires Fody).
Extensions for configuring Autofac with attributes
Configure messages and topology with attributes.
Extend objects with attributes at runtime.
Package Description
Attributes for configuring Autofac registrations
Superset of MEF attributes. In addition to Export/Import contains attributes to support modern IOC (DryIoc) features.
REST API framework so hot it sustains its own wind system. This package installs Stems for ASP.NET Core and the Entity Framework Core data source.
Decorate Stem classes to describe your REST API.
Deprecated. Use Remiworks.Attributes
Provides attributes for the Remiworks event bus framework.
Obsolete! Use https://www.nuget.org/packages/MrAdvice/ instead! MrAdvice allows to weave aspects at build-time (just like PostSharp, but free as in free beer). Write your own aspects in the form of attributes and apply them to target methods or properties.
Registering components into Autofac container using attributes
Create Databases and Tables dynamically just by extending SQLiteModel class and applying proper Attributes. No query Generation Whatsoever. It uses MVC Architecture based Approach, And provides a effective way to create persistent Models.