I found another solution on Scott Hanselman’s blog:
https://www.hanselman.com/blog/CAndNETCoreScriptingWithTheDotnetscriptGlobalTool.aspx
It relies on a .NET CLI tool called dotnet-script, you can find its repository below:
https://github.com/filipw/dotnet-script
To use, it, first install it using dotnet tool install -g dotnet-script
Then you can run dotnet script and use it as a REPL or run dotnet script file.csx to run a file.
To include a NuGet package reference, use #r "nuget: AutoMapper, 6.1.0".