diff --git a/src/dune b/src/dune
index 2dcceea2..ef116a05 100644
--- a/src/dune
+++ b/src/dune
@@ -1,7 +1,7 @@
 (library
  (public_name moonpool)
  (name moonpool)
- (private_modules atomic_ domain_ d_pool_)
+ (private_modules d_pool_)
  (libraries threads either))
 
 (rule
diff --git a/src/moonpool.ml b/src/moonpool.ml
index c44db86b..8bd5d50e 100644
--- a/src/moonpool.ml
+++ b/src/moonpool.ml
@@ -5,3 +5,4 @@ let start_thread_on_some_domain f x =
 module Pool = Pool
 module Fut = Fut
 module Blocking_queue = Bb_queue
+module Atomic = Atomic_
diff --git a/src/moonpool.mli b/src/moonpool.mli
index 783dd00c..ca809bf7 100644
--- a/src/moonpool.mli
+++ b/src/moonpool.mli
@@ -62,3 +62,9 @@ module Blocking_queue : sig
       queue, until it's entirely drained; then [pop] will
       also raise {!Closed}. *)
 end
+
+module Atomic = Atomic_
+(** Atomic values.
+
+    This is either a shim using [ref], on pre-OCaml 5, or the
+    standard [Atomic] module on OCaml 5. *)
diff --git a/test/t_futs1.ml b/test/t_futs1.ml
index 5ee8d113..7f782836 100644
--- a/test/t_futs1.ml
+++ b/test/t_futs1.ml
@@ -1,4 +1,4 @@
-open Moonpool
+open! Moonpool
 
 let pool = Pool.create ~min:4 ()
 let pool2 = Pool.create ~min:2 ()