diff --git a/lib/srfi/139.scm b/lib/srfi/139.scm
index a9e317e3..4198dfba 100644
--- a/lib/srfi/139.scm
+++ b/lib/srfi/139.scm
@@ -7,22 +7,23 @@
 (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 (eval (make-syntactic-closure use-env '() transformer))
-				   use-env))
-		     transformers)))
+           (_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
+                        (eval (make-syntactic-closure use-env '() transformer))
+                        use-env))
+                     transformers)))
       (for-each set-cdr! cells new)
       `(,_let ((,_tmp #f))
          (,_set! ,_tmp (,_let () ,@body))
diff --git a/lib/srfi/139.sld b/lib/srfi/139.sld
index 09ef4cdd..5aa2a866 100644
--- a/lib/srfi/139.sld
+++ b/lib/srfi/139.sld
@@ -1,6 +1,6 @@
 (define-library (srfi 139)
   (export (rename define-syntax define-syntax-parameter)
-	  syntax-parameterize)
+          syntax-parameterize)
   (import (chibi)
-	  (chibi ast))
+          (chibi ast))
   (include "139.scm"))
diff --git a/lib/srfi/139/test.sld b/lib/srfi/139/test.sld
index fb5d8df9..2f6c3607 100644
--- a/lib/srfi/139/test.sld
+++ b/lib/srfi/139/test.sld
@@ -6,47 +6,43 @@
   (begin
     (define-syntax-parameter abort
       (syntax-rules ()
-	((_ . _)
-	 (syntax-error "abort used outside of a loop"))))
-    
+        ((_ . _)
+         (syntax-error "abort used outside of a loop"))))
+
     (define-syntax-parameter foo
       (syntax-rules ()
-	((foo) 'old)))
-    
+        ((foo) 'old)))
+
     (define-syntax forever
       (syntax-rules ()
-	((forever body1 body2 ...)
-	 (call-with-current-continuation
-	  (lambda (escape) 
-	    (syntax-parameterize
-		((abort
-		  (syntax-rules ()
-		    ((abort value (... ...))
-		     (escape value (... ...))))))
-	      (let loop ()
-		body1 body2 ... (loop))))))))
+        ((forever body1 body2 ...)
+         (call-with-current-continuation
+          (lambda (escape) 
+            (syntax-parameterize
+             ((abort
+               (syntax-rules ()
+                 ((abort value (... ...))
+                  (escape value (... ...))))))
+             (let loop ()
+               body1 body2 ... (loop))))))))
 
     (define (run-tests)
       (test-begin "srfi-139: syntax parameters")
 
       (test (list 'old 'new)
-	    (let ((new
-		   (syntax-parameterize
-		       ((foo (syntax-rules ()
-			       ((foo) 'new))))
-		     (foo))))
-	      (list (foo) new)))
+          (let ((new
+                 (syntax-parameterize
+                  ((foo (syntax-rules ()
+                          ((foo) 'new))))
+                  (foo))))
+            (list (foo) new)))
 
-      
       (test 10
-	    (let ((i 0))
-	      (forever
-	       (set! i (+ 1 i))
-	       (when (= i 10)
-		 (abort)))
-	      i))
-
-
-      
+          (let ((i 0))
+            (forever
+             (set! i (+ 1 i))
+             (when (= i 10)
+               (abort)))
+            i))
 
       (test-end))))