Top 20 NuGet http Packages

Routable is a simple, easy to use, request routing library. It is platform agnostic and designed to easily integrate with whatever platform you prefer.
Client for calling HTTP REST APIs, mapping HTTP responses to C# types using a fluent API
Core utility functions for web applications
Simple Http and Object caching
Provides a proxy like HttpContent implementation that reports the upload progress.
Quick wrapper around c# http stuff
Interfaces Remote Controller commands (Karpach.Remote.Commander)
Kraken library for working with HTTP clients.
Web Http (api)
Redistributable components for package 'poco.net'. This package should only be installed as a dependency. (This is not the package you are looking for).
The library exposes an asynchronous HTTP request and response parser.
Deveel REST Client
The Connection-Based Asynchronous Messaging (CBAM) HTTP package contains API to send HTTP requests from client to server. The HTTP API itself is minimalistic and easy-to-use.
This package uses and augments Backend.Core.Initialization package for initializing HTTP server of Backend.HTTP.Server package.
Contains Kestrel-based HTTP server which uses modules implementing interfaces defined in Backend.Core package to generate response to clients.
This package contains Backend HTTP module to statically serve files from filesystem.
Generic login module for backend HTTP servers, configurable to use multiple login providers to authenticate user.
Contains class implementing StringTransformer interface from Backend.HTTP.Common package, which uses cryptographic digests (e.g. SHA512) to transform strings.