However, after I got QuickLisp loaded, I tried: (ql:quickload :cl-ppcre) and got the following error:
> (ql:quickload :cl-ppcre)To load "cl-ppcre":
  Load 1 ASDF system:
    cl-ppcre
; Loading "cl-ppcre"
.
;;; Error: in file /home/blake/quicklisp/dists/quicklisp/software/cl-ppcre-20230618-git/convert.lisp, end position 14464,
;;;     and form: (DEFUN MAYBE-ACCUMULATE (STR) ...)
;;;   The function SI::FUNCTION-RETURN-TYPE is undefined.
;;; Compilation failed!
Debugger called in: #<thread "Initial" active (16383) 0x7fdeeaa93740 7fdee30f9000>.
#<a UIOP/LISP-BUILD:COMPILE-FILE-ERROR 140594891262688>:
    COMPILE-FILE-ERROR while compiling #<ASDF/LISP-ACTION:CL-SOURCE-FILE "cl-ppcre" "convert">
Available restarts:
Command   Restart Name        Description
:r1       RETRY               Retry compiling #<ASDF/LISP-ACTION:CL-SOURCE-FILE "cl-ppcre" "convert">.
:r2       ACCEPT              Continue, treating compiling #<ASDF/LISP-ACTION:CL-SOURCE-FILE "cl-ppcre" "convert"> as having been successful.
:r3       RETRY               Retry ASDF operation.
:r4       CLEAR-CONFIGURATION-AND-RETRY Retry ASDF operation after resetting the configuration.
:r5       RETRY               Retry ASDF operation.
:r6       CLEAR-CONFIGURATION-AND-RETRY Retry ASDF operation after resetting the configuration.
:r7       ABORT               Give up on "cl-ppcre"
:r8       REGISTER-LOCAL-PROJECTS Register local projects and try again.
:r9       RESTART-TOPLEVEL    Go back to Top-Level REPL.
:r10      ABORT               Abort this computation: (SI:TOP-APPLY SI:SAFE-EVAL (SI:TOP-LEVEL) NIL -7).
:r11      TERMINATE-THREAD    Terminate this thread: #<thread "Initial" active (16383) 0x7fdeeaa93740 7fdee30f9000>.
Type :h for Help.
Broken at IHS[14]> LAMBDA. In: #<thread "Initial" active (16383) 0x7fdeeaa93740 7fdee30f9000>.
 File: "/home/blake/quicklisp/quicklisp/setup.lisp" (Position #6166)
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