diff --git a/Source/Threading/AuWakeOnAddress.cpp b/Source/Threading/AuWakeOnAddress.cpp
index b094b7e9..2e722f42 100644
--- a/Source/Threading/AuWakeOnAddress.cpp
+++ b/Source/Threading/AuWakeOnAddress.cpp
@@ -81,7 +81,9 @@ namespace Aurora::Threading
 
     bool WaitEntry::SleepOn(WaitState &state)
     {
+    #if !defined(WOA_SEMAPHORE_MODE)
         AU_LOCK_GUARD(this->mutex);
+    #endif
 
         if (state.qwNanosecondsAbs)
         {
@@ -100,8 +102,6 @@ namespace Aurora::Threading
                     return true;
                 }
 
-                auto uTimeRemNS = uEndTime - uNow;
-
             #if defined(AURORA_PLATFORM_WIN32)
                 Win32DropSchedulerResolution();
             #endif
@@ -112,7 +112,12 @@ namespace Aurora::Threading
                 }
                 else
                 {
+                #if defined(WOA_SEMAPHORE_MODE)
+                    this->semaphore->LockAbsNS(uEndTime);
+                #else
+                    auto uTimeRemNS = uEndTime - uNow;
                     this->variable.WaitForSignalNsEx(&this->mutex, uTimeRemNS);
+                #endif
                 }
 
                 uNow = AuTime::SteadyClockNS();
@@ -130,7 +135,11 @@ namespace Aurora::Threading
                 }
                 else
                 {
+                #if defined(WOA_SEMAPHORE_MODE)
+                    this->semaphore->Lock();
+                #else
                     this->variable.WaitForSignalNsEx(&this->mutex, 0);
+                #endif
                 }
             }
 
@@ -147,7 +156,11 @@ namespace Aurora::Threading
             return false;
         }
 
+    #if defined(WOA_SEMAPHORE_MODE)
+        this->semaphore->Unlock(1);
+    #else
         this->variable.Signal();
+    #endif
         return true;
     }
 
@@ -262,10 +275,12 @@ namespace Aurora::Threading
             decltype(pCurrentHead) pLast {};
             while (pCurrentHead)
             {
+            #if !defined(WOA_SEMAPHORE_MODE)
                 // Insertion barrier
                 {
                     AU_LOCK_GUARD(pCurrentHead->mutex);
                 }
+            #endif
 
                 auto [bCont, bRemove] = callback(*pCurrentHead);
 
diff --git a/Source/Threading/AuWakeOnAddress.hpp b/Source/Threading/AuWakeOnAddress.hpp
index fdb1a8a6..7dab5c79 100644
--- a/Source/Threading/AuWakeOnAddress.hpp
+++ b/Source/Threading/AuWakeOnAddress.hpp
@@ -47,8 +47,19 @@ namespace Aurora::Threading
         WaitEntry *pBefore {};
 
         // synch
+    #if defined(WOA_SEMAPHORE_MODE)
+    #if defined(WOA_SEMAPHORE_SEMAPHORE)
+        // PORT: MacOS (?)
+        WOA_SEMAPHORE_SEMAPHORE semaphore;
+    #else
+        // Testing:
+        Primitives::Semaphore semaphore;
+    #endif
+    #else
+        // Recommended (we can better filter spurious wakes for the cost of a barrier on signal):
         Primitives::ConditionMutexInternal mutex; // mutex ctor must come before var
         Primitives::ConditionVariableInternal variable; // ...and something all 2007+ micro and monolithic kernels should have to yield for an event
+    #endif
 
         // state
         const void *pAddress {};