diff --git a/lib/srfi/139.scm b/lib/srfi/139.scm
index f744c105..3fad4fd0 100644
--- a/lib/srfi/139.scm
+++ b/lib/srfi/139.scm
@@ -5,28 +5,28 @@
      (car (cdr expr)))))
 
 (%define-syntax syntax-parameterize
-  (lambda (expr use-env mac-env)
-    (let* ((_let (make-syntactic-closure mac-env '() 'let))
-           (_set! (make-syntactic-closure mac-env '() 'set!))
-           (_out (make-syntactic-closure mac-env '() 'out))
-           (_tmp (make-syntactic-closure mac-env '() 'tmp))
-           (bindings (cadr expr))
-           (body (cddr expr))
-           (keywords (map car bindings))
-           (transformers (map cadr bindings))
-           (cells
-            (map (lambda (keyword)
-                   (env-cell use-env keyword))
-                 keywords))
-           (old (map cdr cells))
-           (new (map (lambda (transformer)
-                       (make-macro
-			(make-transformer
-			 (eval
-			  (make-syntactic-closure use-env '() transformer)))
-                        use-env))
-                     transformers)))
-      (for-each set-cdr! cells new)
-      `(,_let ((,_tmp #f))
-         (,_set! ,_tmp (,_let () ,@body))
-         (,_out ,_tmp ,cells ,old)))))
+   (lambda (expr use-env mac-env)
+     (let* ((_let (make-syntactic-closure mac-env '() 'let))
+            (_set! (make-syntactic-closure mac-env '() 'set!))
+            (_out (make-syntactic-closure mac-env '() 'out))
+            (_tmp (make-syntactic-closure mac-env '() 'tmp))
+            (bindings (cadr expr))
+            (body (cddr expr))
+            (keywords (map car bindings))
+            (transformers (map cadr bindings))
+            (cells
+             (map (lambda (keyword)
+                    (env-cell use-env keyword))
+                  keywords))
+            (old (map cdr cells))
+            (new (map (lambda (transformer)
+                        (make-macro
+                         (make-transformer
+                          (eval
+                           (make-syntactic-closure use-env '() transformer)))
+                         use-env))
+                      transformers)))
+       (for-each set-cdr! cells new)
+       `(,_let ((,_tmp #f))
+          (,_set! ,_tmp (,_let () ,@body))
+          (,_out ,_tmp ,cells ,old)))))