Perhaps because I'm still on Debian 12 (or more likely I did something wrong), I had trouble getting it working by compiling the icl/ocicl sources with sbcl. It complained "Failed to connect to Slynk after 10 seconds". I tried running a Slynk server in sbcl, but icl froze up, and the server said "slynk:close-connection: end of file on #<dynamic-extent STRING-INPUT-STREAM (unavailable) from "#A">. Then I tried running a swank server, and got the icl prompt (good), but then tab completion invoked the debugger: "Package SLYNK does not exist". Finally, I ran the swank server after first running "(asdf:load-system :slynk)" and everything seems to work.
One thing I immediately miss (that rlwrap provides) are the keyboard functions such as reverse-search-history (usually mapped to C-r) and history-search-backward (have this mapped to M-p). History recall only seems possible with the up arrow.
Also, be in for some surprises if you try to paste some lisp code into the REPL, especially if there are long lines. The interaction is apparently meant for a human typing, not pasting.
One thing I immediately miss (that rlwrap provides) are the keyboard functions such as reverse-search-history (usually mapped to C-r) and history-search-backward (have this mapped to M-p). History recall only seems possible with the up arrow.
Also, be in for some surprises if you try to paste some lisp code into the REPL, especially if there are long lines. The interaction is apparently meant for a human typing, not pasting.