diff --git a/guix-data-service/web/server.scm b/guix-data-service/web/server.scm
index c375634..5507346 100644
--- a/guix-data-service/web/server.scm
+++ b/guix-data-service/web/server.scm
@@ -174,7 +174,8 @@ port. Also, the port used can be changed by passing the --port option.\n"
                          (open-postgresql-connection
                           "background"
                           postgresql-statement-timeout))
-                       4
+                       (max (floor (/ postgresql-connections 5))
+                            1)
                        #:name "background"
                        #:idle-seconds 5
                        #:destructor