I think Kotlin is pretty close to that albeit not satisfying (D) and only satisfying (E) if you use a pauseless GC (which you can do, it's just one command line

I think Kotlin is pretty close to that albeit not satisfying (D) and only satisfying (E) if you use a pauseless GC (which you can do, it's just one command line flag). The pervasive use of type inference gives it a Pythonic feel. My company has a private tool called hshell that's completely replaced bash for my own use. It uses Kotlin Scripting to provide hashbang script-style development along with a UNIX-like API with functions like cp, cd, ls, find, tar, zip, ssh etc. You can also do things like print markdown to the console and it'll be formatted, and it understands how to draw progress bars from various sources like file copies or loop iterators. You can depend on libraries by just adding @file:DependsOn("io.ktor:ktor-server-{netty,core}-jvm:2.0.2") to the top of the file, IntelliJ can give full intellisense and refactoring support for these scripts, they're portable, you can define a CLI by annotating variables and there's a variety of other useful features. As it runs on the JVM you also get auto-vectorization, although why you'd want that for one-off scripts I'm not quite sure. It doesn't have zero cost abstractions. As you note, combining all those features together is rather hard if you want to keep a lightweight scripting feel. Overall it's pretty nice. I wouldn't want to go back to bash or python, the ergonomics of hshell are far better. I'm not sure what to do with it though, maybe release it as a product (but at what price? is there any demand?). I'm pretty sure I don't want to sign up for open source maintenance duties right now.