Professor X: For someone who hates mutants... you certainly keep some strange company. William Stryker: Oh, they serve their purpose... as long as they can be controlled.

Stryker.NET offers you mutation testing for your .NET Core and .NET Framework projects. It allows you to test your tests by temporarily inserting bugs.

For an introduction to mutation testing and Stryker's features, see stryker-mutator.io. Looking for mutation testing in JavaScript & Typescript or Scala?

Stryker.NET is installed using NuGet as a dotnet core global tool. Stryker.NET can be installed in one of these ways:

dotnet tool install -g dotnet-stryker

Starting from dotnet core 3.0 dotnet tools can also be installed on a project level. This requires the following steps:

Create a file called dotnet-tools.json in your project folder. You can checkin to version control to make sure all team members have access to stryker

dotnet new tool-manifest

Then install stryker without the -g flag while executing the following command in the project folder

dotnet tool install dotnet-stryker

Now you can run Stryker.NET from your test project directory by executing:

dotnet stryker

For the full documentation on how to use Stryker.NET, see our configuration docs.

Dotnet global tools do not auto update. To update stryker as a global tool run dotnet tool update --global dotnet-stryker. Stryker will notify you when a new version is available on every run.

The old way of installing stryker is deprecated and replaced by the dotnet core tool. For a guide on how to upgrade see our blog.

Runs on test projects targeting:

• netcoreapp 1.1+
• netframework 4.5+

Dotnet core runtime 2.2+ needs to be available on your system to run dotnet stryker.

For .NET Framework projects, Stryker.NET requires nuget.exe to be installed on your system. Please follow their installation instructions.

Right now, Stryker.NET supports the following mutations:

• Arithmetic Operators
• Equality Operators
• Boolean Literals
• Assignment statements
• Unary Operators
• Update Operators
• Checked Statements
• Linq Methods
• String Literals
• Bitwise Operators

For the full list of all available mutations, see the mutator docs.

• Html reporter
• Dashboard reporter
• Console reporter
• Progress reporter
• Console dots reporter
• Json reporter

For the full list of all available reporters, see the reporter docs.

Want to help develop Stryker.NET? Check out our contribution guide.