diff --git Utilities/cmlibuv/src/unix/core.c Utilities/cmlibuv/src/unix/core.c
index a357ef3..135b7bb 100644
--- Utilities/cmlibuv/src/unix/core.c
+++ Utilities/cmlibuv/src/unix/core.c
@@ -1293,9 +1293,12 @@ int uv_os_unsetenv(const char* name) {
   if (name == NULL)
     return UV_EINVAL;
 
+#if ( defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED < 1050)
+    unsetenv(name);
+#else
   if (unsetenv(name) != 0)
     return UV__ERR(errno);
-
+#endif
   return 0;
 }
 
diff --git Utilities/cmlibuv/src/unix/fs.c Utilities/cmlibuv/src/unix/fs.c
index a6cc6db..420490a 100644
--- Utilities/cmlibuv/src/unix/fs.c
+++ Utilities/cmlibuv/src/unix/fs.c
@@ -60,7 +60,7 @@
 # include <sys/sendfile.h>
 #endif
 
-#if defined(__APPLE__)
+#if ( defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1050 )
 # include <copyfile.h>
 #elif defined(__linux__) && !defined(FICLONE)
 # include <sys/ioctl.h>
@@ -674,7 +674,7 @@ static ssize_t uv__fs_sendfile(uv_fs_t* req) {
 
     return -1;
   }
-#elif defined(__APPLE__)           || \
+#elif defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1050           || \
       defined(__DragonFly__)       || \
       defined(__FreeBSD__)         || \
       defined(__FreeBSD_kernel__)
@@ -825,7 +825,7 @@ done:
 }
 
 static ssize_t uv__fs_copyfile(uv_fs_t* req) {
-#if defined(__APPLE__) && !TARGET_OS_IPHONE
+#if ( defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1050) && !TARGET_OS_IPHONE
   /* On macOS, use the native copyfile(3). */
   copyfile_flags_t flags;
 
@@ -984,7 +984,7 @@ static void uv__to_stat(struct stat* src, uv_stat_t* dst) {
   dst->st_blksize = src->st_blksize;
   dst->st_blocks = src->st_blocks;
 
-#if defined(__APPLE__)
+#if ( defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1050)
   dst->st_atim.tv_sec = src->st_atimespec.tv_sec;
   dst->st_atim.tv_nsec = src->st_atimespec.tv_nsec;
   dst->st_mtim.tv_sec = src->st_mtimespec.tv_sec;