--- a/src/fsevents/fsevents_stubs.c	2022-10-19 21:58:04
+++ b/src/fsevents/fsevents_stubs.c	2024-02-21 14:57:28
@@ -7,7 +7,11 @@
 #include <caml/threads.h>
 
 #if defined(__APPLE__)
+#include <AvailabilityMacros.h>
+#endif
 
+#if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 101000
+
 #include <Availability.h>
 #include <CoreFoundation/CoreFoundation.h>
 #include <CoreServices/CoreServices.h>
@@ -88,7 +92,7 @@
       continue;
     }
     CFStringRef cf_path;
-#if __MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
     CFDictionaryRef details = CFArrayGetValueAtIndex(eventPaths, i);
     cf_path = CFDictionaryGetValue(details, kFSEventStreamEventExtendedDataPathKey);
 #else
@@ -154,7 +158,7 @@
 
   const FSEventStreamEventFlags flags =
       kFSEventStreamCreateFlagNoDefer |
-#if __MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
       kFSEventStreamCreateFlagUseExtendedData |
 #endif
       kFSEventStreamCreateFlagUseCFTypes | kFSEventStreamCreateFlagFileEvents;
@@ -331,7 +335,12 @@
 
 #else
 
-static char *unavailable_message = "fsevents is only available on macos";
+static char *unavailable_message =
+#if defined(__APPLE__)
+    "upgrade your macos sdk to enable watch mode";
+#else
+    "fsevents is only available on macos";
+#endif
 
 CAMLprim value dune_fsevents_stop(value v_t) {
   caml_failwith(unavailable_message);