diff --git a/guix-data-service/utils.scm b/guix-data-service/utils.scm
index 855c819..c50cb64 100644
--- a/guix-data-service/utils.scm
+++ b/guix-data-service/utils.scm
@@ -99,7 +99,9 @@
 (define (defer-to-thread-pool-channel thunk)
   (make-thread-pool-channel!)
   (let ((reply (make-channel)))
-    (put-message %thread-pool-channel (cons reply thunk))
+    (spawn-fiber
+     (lambda ()
+       (put-message %thread-pool-channel (cons reply thunk))))
     reply))
 
 (define (fetch-result-of-defered-thunk reply-channel)