diff --git a/src/mem/util/mem_utils.c b/src/mem/util/mem_utils.c
index 87889c6..e642e9b 100644
--- a/src/mem/util/mem_utils.c
+++ b/src/mem/util/mem_utils.c
@@ -65,6 +65,11 @@ void *wapp_mem_util_align_forward(void *ptr, u64 alignment) {
 void *wapp_mem_util_alloc(u64 size, MemAccess access, MemAllocFlags flags,
                           MemInitType type) {
 #if defined(WAPP_PLATFORM_WINDOWS)
+  // Ensure memory is committed if it's meant to be initialised
+  if (type == WAPP_MEM_INIT_INITIALISED) {
+    flags |= WAPP_MEM_ALLOC_COMMIT;
+  }
+
   void *output = alloc_windows(size, access, flags);
 #elif defined(WAPP_PLATFORM_POSIX)
   void *output = alloc_posix(size, access, flags);
@@ -99,7 +104,8 @@ internal inline void *alloc_posix(u64 size, MemAccess access,
                                   MemAllocFlags flags) {
   i32 alloc_flags = flags | MAP_ANON | MAP_PRIVATE;
 
-#ifdef WAPP_PLATFORM_LINUX
+#if defined(WAPP_PLATFORM_LINUX) || defined(WAPP_PLATFORM_GNU) ||              \
+    defined(WAPP_PLATFORM_NET_BSD)
   alloc_flags |= MAP_NORESERVE;
 #endif
 
diff --git a/src/mem/util/mem_utils.h b/src/mem/util/mem_utils.h
index f2a54e8..20c3896 100644
--- a/src/mem/util/mem_utils.h
+++ b/src/mem/util/mem_utils.h
@@ -30,9 +30,16 @@ typedef enum mem_alloc_flags {
 #if defined(WAPP_PLATFORM_WINDOWS)
   WAPP_MEM_ALLOC_RESERVE = MEM_RESERVE,
   WAPP_MEM_ALLOC_COMMIT = MEM_COMMIT,
-#elif defined(WAPP_PLATFORM_POSIX)
+#elif defined(WAPP_PLATFORM_LINUX) || defined(WAPP_PLATFORM_GNU)
   WAPP_MEM_ALLOC_RESERVE = 0,
   WAPP_MEM_ALLOC_COMMIT = MAP_POPULATE,
+#elif defined(WAPP_PLATFORM_FREE_BSD)
+  WAPP_MEM_ALLOC_RESERVE = 0,
+  WAPP_MEM_ALLOC_COMMIT = MAP_PREFAULT_READ,
+#elif defined(WAPP_PLATFORM_BSD) || defined(WAPP_PLATFORM_UNIX) ||             \
+    defined(WAPP_PLATFORM_APPLE)
+  WAPP_MEM_ALLOC_RESERVE = 0,
+  WAPP_MEM_ALLOC_COMMIT = 0,
 #endif
 } MemAllocFlags;