diff --git a/rmacs/buffer.rkt b/rmacs/buffer.rkt
index c4ec118..06700e8 100644
--- a/rmacs/buffer.rkt
+++ b/rmacs/buffer.rkt
@@ -55,13 +55,9 @@
          buffer-local
          define-buffer-local
 
-         command?
-         command-selector
-         command-buffer
-         command-window
-         command-editor
+         (except-out (struct-out command) command)
+         copy-command
          (rename-out [make-command command])
-         replace-selector
          invoke
 
          define-key
@@ -410,8 +406,20 @@
                   [(command? buffer-or-command) (command-buffer buffer-or-command)]))
   (command selector buffer window (or editor (buffer-editor buffer)) keyseq prefix-arg))
 
-(define (replace-selector cmd selector)
-  (struct-copy command cmd [selector selector]))
+(define (copy-command cmd
+                      #:selector [selector (command-selector cmd)]
+                      #:buffer [buffer (command-buffer cmd)]
+                      #:window [window (command-window cmd)]
+                      #:editor [editor (command-editor cmd)]
+                      #:keyseq [keyseq (command-keyseq cmd)]
+                      #:prefix-arg [prefix-arg (command-prefix-arg cmd)])
+  (struct-copy command cmd
+               [selector selector]
+               [buffer buffer]
+               [window window]
+               [editor editor]
+               [keyseq keyseq]
+               [prefix-arg prefix-arg]))
 
 (define (invoke cmd)
   (match-define (command selector buf _ _ keyseq _) cmd)
diff --git a/rmacs/mode/fundamental.rkt b/rmacs/mode/fundamental.rkt
index 0c9346c..21014fe 100644
--- a/rmacs/mode/fundamental.rkt
+++ b/rmacs/mode/fundamental.rkt
@@ -12,12 +12,19 @@
   (match keyseq
     [(list (key (? char? ch) modifiers)) #:when (set-empty? (set-remove modifiers 'shift))
      (buffer-insert! buf (window-point win) (string->rope (string ch)))]
+    [(list (key (? char? ch0) modifiers)) #:when (equal? modifiers (set 'control))
+     (define ch (integer->char (- (char->integer (char-upcase ch0)) (char->integer #\A) -1)))
+     (buffer-insert! buf (window-point win) (string->rope (string ch)))]
     [_ #f]))
 
 (define-command fundamental-mode (unbound-key-sequence buf #:command cmd #:keyseq keyseq)
-  (invoke (replace-selector cmd 'self-insert-command)))
+  (invoke (copy-command cmd #:selector 'self-insert-command)))
 
-(define-key fundamental-mode (list "C-q" '#:default) self-insert-command)
+(define-command fundamental-mode (quoted-insert buf #:command cmd #:keyseq keyseq)
+  #:bind-key "C-q #:default"
+  (invoke (copy-command cmd
+                        #:selector 'self-insert-command
+                        #:keyseq (list (cadr keyseq)))))
 
 (define-command fundamental-mode (newline buf #:window win)
   #:bind-key "C-m"