Type Profiler is a type inference tool for plain Ruby code. It analyzes Ruby code that has no type information and guesses a type of the modules and methods in the code. The output will serve as a signature for external type checkers like Sorbet and Steep. Since 2019, we have been developing the tool as one of the key features for Ruby 3 static analysis, and now it works with some practical applications. In this talk, we briefly explain what and how Type Profiler works, present a roadmap and progress of the development, and discuss how useful it is for practical applications with some demos.