Yeah, cider has an amazing form by form debugger for Clojure. And the way cider uses overlays to surface this is quite nice too.

My general experience of cider is that for a certain set of tasks it is much better than slime. But, the problem is, most of my day-to-day coding tasks are hampered by the language: e.g. if I have a web server running and I want to change a request handler, you can’t just recompile the handler, you also have to restart the server.

(Although, if you anticipate this, you can call the ref (e.g. `(#’foo arg)`) rather than the function `(foo arg)`. But this means that you have to plan the dynamically modifiable parts out ahead of time.

That's not true. You only have to prepend #' if you pass the function by value (as in your web server handler example).

If you call the function by name yourself, like (foo arg), and you recompile foo, any code that called foo will see the new version.

Hmm, I’ll try it again, but I remember issues with the function call syntax too. Iirc, it had to do with the fact that redefinitions don’t count if the use site is running in another thread. But I’ll double-check this when I get a chance.