diff --git a/asymptote.rkt b/asymptote.rkt
index be9409a5a..226c19a0d 100644
--- a/asymptote.rkt
+++ b/asymptote.rkt
@@ -8,9 +8,7 @@
 
 (define (asymptote #:cache [cache? #t] s . strs)
   (define single-str
-    (with-output-to-string
-     (lambda () (for ([str (in-list `(,s . ,strs))])
-                  (displayln str)))))
+    (string-append (apply ~a #:separator "\n" s strs) "\n"))
   (if cache?
       ;; cache:
       (let* ([asymptote-dir "asymptote-images"]
@@ -54,4 +52,4 @@
          (λ ()
            ;(with-output-to-string
            (system (format "asy -v -f png -o ~a" tmp-file))))
-        tmp-file))) ; HTML png PDF pdf
\ No newline at end of file
+        tmp-file))) ; HTML png PDF pdf