I still haven't found an environment which lets you build the system as seamlessly as SBCL. The REPL allows you to build the code at runtime and update the system in place. Since I was a solodev, bug fixing and building the thing without going on the wrong path was worth I think months and years of my time.
edit: Once you get the idea of a running Lisp image and you are updating the image it's a game changer. You are not writing a program, then compiling it and then running it anymore (even though those steps happen seamlessly).
edit: Once you get the idea of a running Lisp image and you are updating the image it's a game changer. You are not writing a program, then compiling it and then running it anymore (even though those steps happen seamlessly).