REPL driven development We can develop our program while it's running. And it's not a tricky thing that injects or restart anything, it's by design. Load file

REPL driven development We can develop our program while it's running. And it's not a tricky thing that injects or restart anything, it's by design. Load file to REPL and now your functions are redefined. Just on this namespace. Load file/reload isn't a automagical thing. It's simple: just "stream" your file to the REPL. HTTP library, DB library, any library need to thing about "how do I hot reload", it's a language feature. I see many developers arguing things like "types are important because avoid runtime errors". If you develop INSIDE runtime, you have no reason to fear runtime errors. Your runtime error will blow up during development process. A cool thing about this pieces: - I can start my app from REPL - Connect my browser in this app - Run my integration tests that create entities (inside the same REPL) - See in the browser the state from app after run the test.