Top 20 NuGet guard Packages

Catel.Core library.
A simple package by @ardalis and @nimblepros with guard clause helper methods. See docs for how to extend using your own extension methods defined in your project.
A simple library that facilitates runtime checks of code and allows to define preconditions and invariants within a method.
Roslyn analyzers that aim to help security audits on .NET applications.
A high-performance, extensible argument validation library.
Evolved toolkit for developing applications faster and with less code. Includes general purpose extension methods, guard clauses, predefined value objects (PasswordHash,Email, Percentage etc) and specialized helper classes for specific tasks.
Argument validation made simple and unified. It ensures arguments conforms to simple validation rules and provides an uniformed exception throwing strategy if arguments are invalid.
A guard implementation that performs asserts/assumptions to prevent invalid code execution.
A .NET library that provides a variety of reusable functionality, including packed integers (PackedInt16, PackedInt32, and PackedInt64), guard methods, various extension methods, and classes related to the Task Parallel Library (AsyncLazy, AsyncLock, AsyncAutoResetEvent, and AsyncManualResetEvent).
PraxiCloud libraries offer a range of common functions, features and base classes to use when building solutions, increasing the time to delivery.
Simple Guard (or DbC) implementation.
A simple guard library for validating method parameters without being a complete validation library. This library makes it easy to validate method arguments in a uniform way.
Deep fork of the Seterlund.CodeGuard library. Example: Guard.That(arg1).IsNotNull().GreaterThan(100); Throws an exception if conditions are not met.
Guard and Validator library. Example: Guard.That(arg1).IsNotNull().GreaterThan(100); Throws an exception if conditions are not met. Supports the ability to get a list of the failed conditions.
LeadPipe.Net is a collection of useful types, patterns, and extensions. These include a guarding type, tracking observable collection, command mediator, poller, and finite state machine. LeadPipe.Net is an open source collection of useful tools for .NET development. Read more about the ...
guard check assert
.NET Core port of Seterlund.CodeGuard, a Guard and Validator library. Example: Guard.That(arg1).IsNotNull().GreaterThan(100); Throws an exception if conditions are not met. Supports the ability to get a list of the failed conditions.
.NET Core 2.0 & Standard 2.0 port of A simple guard clause project helping you with validation and uniformed exception throwing when validating arguments.
An easy-to-use management system for the ASP.NET Membership system built for ASP.NET MVC 5 applications. This application comes complete with an Area, Controllers, Views and everything you need to start managing your ASP.NET MVC 5 application immediately.
Provides performant guard functionality for methods to throw exceptions