diff --git a/gnu/services/configuration.scm b/gnu/services/configuration.scm
index 2b3bd4c1f4..10cb933ed1 100644
--- a/gnu/services/configuration.scm
+++ b/gnu/services/configuration.scm
@@ -436,7 +436,11 @@ the list result in @code{#t} when applying PRED? on them."
 (define list-of-strings?
   (list-of string?))
 
-(define alist? list?)
+(define alist?
+  (match-lambda
+    (() #t)
+    ((head . tail) (and (pair? head) (alist? tail)))
+    (_ #f)))
 
 (define serialize-file-like empty-serializer)