It seems like image-based interactive development is on a spectrum from "less alive" edit-compile-run, adding some interactivity with tools like gdb, continuing up through IDEs and REPLs, and up through Elm/Dart-style hot code reloading and BEAM-style runtime module reloading.

Maybe CL's flavor of image based development is just an example of good ergonomics, because the fundamental interactions (edit, compile, update image, test, repeat) are not really different from developing a C program inside a Docker container.