diff --git a/gnu/home/services/sway.scm b/gnu/home/services/sway.scm
index 835053de1af..fcddbdbea20 100644
--- a/gnu/home/services/sway.scm
+++ b/gnu/home/services/sway.scm
@@ -129,9 +129,6 @@
 (define (list-of-string-ish? lst)
   (every string-ish? lst))
 
-(define (list-of-packages? lst)
-  (every package? lst))
-
 (define (bar-position? p)
   (member p '(top bottom)))
 
diff --git a/gnu/services/configuration.scm b/gnu/services/configuration.scm
index 886847b9bb7..d42f04f1161 100644
--- a/gnu/services/configuration.scm
+++ b/gnu/services/configuration.scm
@@ -535,7 +535,10 @@ the list result in @code{#t} when applying PRED? on them."
           #f)))
 
 (define list-of-packages?
-  (list-of package?))
+  (list-of (match-lambda
+             ((? package? pkg) #t)
+             (((? package? pkg) output) #t)
+             (_ #f))))
 
 (define list-of-strings?
   (list-of string?))