Sorbet: Typed Ruby with Dmitry Petrashko

Programming languages are dynamically typed or statically typed. In a dynamically typed language, the programmer does not need to declare if a variable is an integer, string, or other type. In a statically typed language, the developer must declare the type of the variable upfront, so that the compiler can take advantage of that information.

Dynamically typed languages give a programmer flexibility and fast iteration speed. But they also introduce the possibility of errors that can be avoided by performing type checking. This is one of the reasons why TypeScript has risen in popularity, giving developers the option to add types to their JavaScript variables.

Sorbet is a typechecker for Ruby. Sorbet allows for gradual typing of Ruby programs, which helps engineers avoid errors that might otherwise be caused by the dynamic type system. Dmitry Petrashko is an engineer at Stripe who helped build Sorbet. He has significant experience in compilers, having worked on Scala before his time at Stripe. Dmitry joins the show to discuss his work on Sorbet, and the motivation for adding type checking to Ruby.

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