diff --git a/lib/picos_std.sync/conditions.ml b/lib/picos_std.sync/conditions.ml
index 77dc08e6..839a8a92 100644
--- a/lib/picos_std.sync/conditions.ml
+++ b/lib/picos_std.sync/conditions.ml
@@ -1,15 +1,14 @@
 open Picos
 open Picos_std_awaitable
 
-type t = unit Awaitable.t
+type t = int Awaitable.t
 
-let create ?padded () = Awaitable.make ?padded ()
+let create ?padded () = Awaitable.make ?padded 0
 
 let[@inline] wait t lock ~acquire ~release =
-  let trigger = Trigger.create () in
-  let awaiter = Awaitable.Awaiter.add t trigger in
+  let before = Awaitable.get t in
   release lock;
-  let lock_forbidden lock =
+  let lock_forbidden lock ~acquire =
     let fiber = Fiber.current () in
     let forbid = Fiber.exchange fiber ~forbid:true in
     match acquire lock with
@@ -20,12 +19,40 @@ let[@inline] wait t lock ~acquire ~release =
         Fiber.set fiber ~forbid;
         Printexc.raise_with_backtrace exn bt
   in
-  match Trigger.await trigger with
-  | None -> lock_forbidden lock
-  | Some exn_bt ->
-      Awaitable.Awaiter.remove awaiter;
-      lock_forbidden lock;
-      Printexc.raise_with_backtrace (fst exn_bt) (snd exn_bt)
+  let await t lock ~acquire before =
+    match if Awaitable.get t == before then Awaitable.await t before with
+    | () ->
+        let before = Awaitable.get t in
+        if before land 1 = 0 then begin
+          let after = before lor 1 in
+          if
+            (not (Awaitable.compare_and_set t before after))
+            && Awaitable.get t land 1 = 0
+          then Awaitable.signal t
+        end;
+        lock_forbidden lock ~acquire
+    | exception exn ->
+        let bt = Printexc.get_raw_backtrace () in
+        lock_forbidden lock ~acquire;
+        Printexc.raise_with_backtrace exn bt
+  in
+  if before land 1 = 0 then
+    let after = before lor 1 in
+    if Awaitable.compare_and_set t before after || Awaitable.get t == after then
+      await t lock ~acquire after
+    else lock_forbidden lock ~acquire
+  else await t lock ~acquire before
+
+let signal t =
+  let prior = Awaitable.fetch_and_add t 2 in
+  if prior land 1 <> 0 then begin
+    if Awaitable.compare_and_set t (prior + 2) (prior + 1) then ();
+    Awaitable.signal t
+  end
 
-let signal = Awaitable.signal
-let broadcast = Awaitable.broadcast
+let broadcast t =
+  let prior = Awaitable.fetch_and_add t 2 in
+  if prior land 1 <> 0 then begin
+    if Awaitable.compare_and_set t (prior + 2) (prior + 1) then ();
+    Awaitable.broadcast t
+  end