@db915dd6 ClassTag can give you a Class, which the JVM needs, so yes, that's related to RTTI, but the ClassTag itself is generated by the compiler. I mentioned ClassTag because it's the easiest to use, and you basically get the equivalent of C#'s reification.

That library, izumi-reflect, doesn't have anything to do with a RTTI. All type info is exposed in macros, but AFAIK it's no longer easily accessible as a TypeTag, so you have to write a macro to get it 🤷‍♂️ 

 @db915dd6 BTW, one pretty good development is that you can derive type class instances pretty easily, and you only need "inline" functions with no macros, just compile-time reflection via implicits, which can deconstruct sum and product types.