diff --git a/lib/logging/journald.ml b/lib/logging/journald.ml
index 87980bd..ba08f8e 100644
--- a/lib/logging/journald.ml
+++ b/lib/logging/journald.ml
@@ -36,12 +36,13 @@ let syslog_priority = function
   | ERROR -> "3" (* LOG_ERR *)
 
 let writer t ~ts ~ns ~lvl msg =
+  Mutex.lock t.mutex;
   let dgram =
-    Mutex.protect t.mutex @@ fun () ->
     Buffer.clear t.buf;
     ignore ts;
     add_field t.buf "MESSAGE" (Printf.sprintf "%s: %s" ns msg);
     add_field t.buf "PRIORITY" (syslog_priority lvl);
     Buffer.to_bytes t.buf
   in
+  Mutex.unlock t.mutex;
   Unix.sendto t.sock_fd dgram 0 (Bytes.length dgram) [] t.dest |> ignore
diff --git a/lib/logging/mutex.ml b/lib/logging/mutex.ml
new file mode 100644
index 0000000..7f95264
--- /dev/null
+++ b/lib/logging/mutex.ml
@@ -0,0 +1,5 @@
+(* stub implementation since we actually aren't multithreaded *)
+type t = unit
+external create : unit -> t = "%identity"
+external lock : t -> unit = "%identity"
+external unlock : t -> unit = "%identity"