diff --git a/racket/src/cs/linklet.sls b/racket/src/cs/linklet.sls
index fc0aa48916..69e2f8fce0 100644
--- a/racket/src/cs/linklet.sls
+++ b/racket/src/cs/linklet.sls
@@ -80,7 +80,8 @@
                 environment-variables-ref
                 current-environment-variables
                 find-system-path
-                build-path)
+                build-path
+                format)
           (only (thread)
                 current-process-milliseconds)
           (regexp)
@@ -643,8 +644,8 @@
                                           " reference to a variable that " why ";\n"
                                           " possibly, bytecode file needs re-compile because dependencies changed")
                            "name" (unquoted-printing-string (symbol->string sym))
-                           "exporting instance" (unquoted-printing-string (instance-name inst))
-                           "importing instance" (unquoted-printing-string (instance-name target-inst))))
+                           "exporting instance" (unquoted-printing-string (format "~a" (instance-name inst)))
+                           "importing instance" (unquoted-printing-string (format "~a" (instance-name target-inst)))))
 
   (define (identify-module var)
     (let ([i (car (variable-inst-box var))])
diff --git a/racket/src/schemify/schemify.rkt b/racket/src/schemify/schemify.rkt
index b62caf4bfb..ae518647c9 100644
--- a/racket/src/schemify/schemify.rkt
+++ b/racket/src/schemify/schemify.rkt
@@ -211,14 +211,19 @@
                                      for-cify? for-jitify?
                                      unsafe-mode?))
         (match form
-          [`(define-values ,ids ,_)
+          [`(define-values ,ids ,rhs)
+           (define simple-rhs? (simple? rhs prim-knowns knowns imports mutated))
            (append
-            (if (or for-jitify? for-cify?)
-                (reverse accum-exprs)
-                (make-expr-defns accum-exprs))
+            (let ([accum-exprs (if simple-rhs?
+                                   accum-exprs
+                                   (append (make-set-variables)
+                                           accum-exprs))])
+              (if (or for-jitify? for-cify?)
+                  (reverse accum-exprs)
+                  (make-expr-defns accum-exprs)))
             (cons
              schemified 
-             (let id-loop ([ids ids] [accum-exprs null] [accum-ids accum-ids])
+             (let id-loop ([ids ids] [accum-exprs null] [accum-ids (if simple-rhs? accum-ids null)])
                (cond
                 [(wrap-null? ids) (loop (wrap-cdr l) mut-l accum-exprs accum-ids)]
                 [(or (or for-jitify? for-cify?)
@@ -235,13 +240,17 @@
                 [else
                  (id-loop (wrap-cdr ids) accum-exprs (cons (unwrap (wrap-car ids)) accum-ids))]))))]
           [`,_
-           ;; In case `schemified` triggers an error, sync exported variables
-           (define set-vars (make-set-variables))
            (cond
-             [(null? set-vars)
-              (loop (wrap-cdr l) mut-l (cons schemified accum-exprs) null)]
+             [(simple? form prim-knowns knowns imports mutated)
+              (loop (wrap-cdr l) mut-l (cons schemified accum-exprs) accum-ids)]
              [else
-              (loop (wrap-cdr l) mut-l (cons schemified (append (reverse set-vars) accum-exprs)) null)])])])))
+              ;; In case `schemified` triggers an error, sync exported variables
+              (define set-vars (make-set-variables))
+              (cond
+                [(null? set-vars)
+                 (loop (wrap-cdr l) mut-l (cons schemified accum-exprs) null)]
+                [else
+                 (loop (wrap-cdr l) mut-l (cons schemified (append (reverse set-vars) accum-exprs)) null)])])])])))
   ;; Return both schemified and known-binding information, where
   ;; the later is used for cross-linklet optimization
   (values schemified knowns mutated))