A tool to effectively run the RegexOptions.Compiled compilation at build time, rather than at runtime, and directly embed the generated code in your assembly.
The code for Regex compilation was taken directly from corefx at dotnet/corefx/src/System.Text.RegularExpressions@17382de and then modified to suit the purpose of this project.
In essence, the lightweight-codegen done to generate IL directly at runtime is modified to generate broadly equivalent C# code, which is generated from the regex during the build, and included in the project directly as generated C# code.