diff --git a/src/core/CCEqual.ml b/src/core/CCEqual.ml
index 90c98cbc..f879bd05 100644
--- a/src/core/CCEqual.ml
+++ b/src/core/CCEqual.ml
@@ -11,6 +11,7 @@ let int : int t = (=)
 let string : string t = (=)
 let bool : bool t = (=)
 let float : float t = (=)
+let unit () () = true
 
 let rec list f l1 l2 = match l1, l2 with
   | [], [] -> true
diff --git a/src/core/CCEqual.mli b/src/core/CCEqual.mli
index 6eb5fa9d..8c1d4adc 100644
--- a/src/core/CCEqual.mli
+++ b/src/core/CCEqual.mli
@@ -15,6 +15,7 @@ val int : int t
 val string : string t
 val bool : bool t
 val float : float t
+val unit : unit t
 
 val list : 'a t -> 'a list t
 val array : 'a t -> 'a array t