diff --git a/DepotDownloader/ContentDownloader.cs b/DepotDownloader/ContentDownloader.cs
index 68ad7ae5..38d73fd6 100644
--- a/DepotDownloader/ContentDownloader.cs
+++ b/DepotDownloader/ContentDownloader.cs
@@ -1037,7 +1037,8 @@ namespace DepotDownloader
             FileStream fs = null;
             List<ProtoManifest.ChunkData> neededChunks;
             var fi = new FileInfo(fileFinalPath);
-            if (!fi.Exists)
+            var fileDidExist = fi.Exists;
+            if (!fileDidExist)
             {
                 Console.WriteLine("Pre-allocating {0}", fileFinalPath);
 
@@ -1183,16 +1184,14 @@ namespace DepotDownloader
                 }
             }
 
-            if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+            var fileIsExecutable = file.Flags.HasFlag(EDepotFileFlag.Executable);
+            if (fileIsExecutable && (!fileDidExist || oldManifestFile == null || !oldManifestFile.Flags.HasFlag(EDepotFileFlag.Executable)))
             {
-                if (file.Flags.HasFlag(EDepotFileFlag.Executable) && (oldManifestFile == null || !oldManifestFile.Flags.HasFlag(EDepotFileFlag.Executable)))
-                {
-                    UnixUtilities.SetExecute(fileFinalPath, true);
-                }
-                else if (oldManifestFile != null && oldManifestFile.Flags.HasFlag(EDepotFileFlag.Executable))
-                {
-                    UnixUtilities.SetExecute(fileFinalPath, false);
-                }
+                PlatformUtilities.SetExecutable(fileFinalPath, true);
+            }
+            else if (!fileIsExecutable && oldManifestFile != null && oldManifestFile.Flags.HasFlag(EDepotFileFlag.Executable))
+            {
+                PlatformUtilities.SetExecutable(fileFinalPath, false);
             }
 
             var fileStreamData = new FileStreamData
diff --git a/DepotDownloader/PlatformUtilities.cs b/DepotDownloader/PlatformUtilities.cs
new file mode 100644
index 00000000..151b2d7b
--- /dev/null
+++ b/DepotDownloader/PlatformUtilities.cs
@@ -0,0 +1,87 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace DepotDownloader
+{
+    public static class PlatformUtilities
+    {
+        [Flags]
+        private enum FilePermissions : uint
+        {
+            S_IXUSR = 0x0040, // Execute by owner
+            S_IXGRP = 0x0008, // Execute by group
+            S_IXOTH = 0x0001, // Execute by other
+            EXECUTE = S_IXGRP | S_IXUSR | S_IXOTH
+        }
+
+        private enum FilePermissionsShort : ushort
+        {
+            S_IXUSR = 0x0040, // Execute by owner
+            S_IXGRP = 0x0008, // Execute by group
+            S_IXOTH = 0x0001, // Execute by other
+            EXECUTE = S_IXGRP | S_IXUSR | S_IXOTH
+        }
+
+        [StructLayout(LayoutKind.Explicit, Size = 144)]
+        private readonly struct StatLinux
+        {
+            [FieldOffset(24)] public readonly FilePermissions st_mode;
+        }
+
+        [StructLayout(LayoutKind.Explicit, Size = 144)]
+        private readonly struct StatOSX
+        {
+            [FieldOffset(4)] public readonly FilePermissionsShort st_mode;
+        }
+
+        [DllImport("libc", EntryPoint = "__xstat", SetLastError = true)]
+        private static extern int stat(int version, string path, out StatLinux statLinux);
+
+        [DllImport("libc", EntryPoint = "stat$INODE64", SetLastError = true)]
+        private static extern int stat(string path, out StatOSX stat);
+
+        [DllImport("libc", SetLastError = true)]
+        private static extern int chmod(string path, FilePermissions mode);
+
+        [DllImport("libc", SetLastError = true)]
+        private static extern int chmod(string path, FilePermissionsShort mode);
+
+        [DllImport("libc", CallingConvention = CallingConvention.Cdecl, SetLastError = true)]
+        private static extern IntPtr strerror(int errno);
+
+        private static void ThrowIf(int i)
+        {
+            if (i == -1)
+            {
+                var errno = Marshal.GetLastWin32Error();
+                throw new Exception(Marshal.PtrToStringAnsi(strerror(errno)));
+            }
+        }
+
+        public static void SetExecutable(string path, bool value)
+        {
+            if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
+            {
+                ThrowIf(PlatformUtilities.stat(1, path, out var stat));
+
+                if (stat.st_mode.HasFlag(FilePermissions.EXECUTE) != value)
+                {
+                    ThrowIf(chmod(path, value
+                        ? stat.st_mode | FilePermissions.EXECUTE
+                        : stat.st_mode & ~FilePermissions.EXECUTE));
+                }
+            }
+            else if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX))
+            {
+                ThrowIf(PlatformUtilities.stat(path, out var stat));
+
+                if (stat.st_mode.HasFlag(FilePermissionsShort.EXECUTE) != value)
+                {
+                    ThrowIf(chmod(path, value
+                        ? stat.st_mode | FilePermissionsShort.EXECUTE
+                        : stat.st_mode & ~FilePermissionsShort.EXECUTE));
+                }
+            }
+        }
+    }
+}
diff --git a/DepotDownloader/UnixUtilities.cs b/DepotDownloader/UnixUtilities.cs
deleted file mode 100644
index 3935d973..00000000
--- a/DepotDownloader/UnixUtilities.cs
+++ /dev/null
@@ -1,80 +0,0 @@
-using System;
-using System.Runtime.InteropServices;
-
-namespace DepotDownloader
-{
-    public static class UnixUtilities
-    {
-        [Flags]
-        private enum FilePermissions : uint
-        {
-            S_ISUID = 0x0800, // Set user ID on execution
-            S_ISGID = 0x0400, // Set group ID on execution
-            S_ISVTX = 0x0200, // Save swapped text after use (sticky).
-            S_IRUSR = 0x0100, // Read by owner
-            S_IWUSR = 0x0080, // Write by owner
-            S_IXUSR = 0x0040, // Execute by owner
-            S_IRGRP = 0x0020, // Read by group
-            S_IWGRP = 0x0010, // Write by group
-            S_IXGRP = 0x0008, // Execute by group
-            S_IROTH = 0x0004, // Read by other
-            S_IWOTH = 0x0002, // Write by other
-            S_IXOTH = 0x0001, // Execute by other
-
-            S_IRWXU = S_IRUSR | S_IWUSR | S_IXUSR,
-            S_IRWXG = S_IRGRP | S_IWGRP | S_IXGRP,
-            S_IRWXO = S_IROTH | S_IWOTH | S_IXOTH,
-            ACCESSPERMS = S_IRWXU | S_IRWXG | S_IRWXO, // 0777
-            ALLPERMS = S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO, // 07777
-            DEFFILEMODE = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH, // 0666
-            EXECUTE = S_IXGRP | S_IXUSR | S_IXOTH,
-
-            // Device types
-            S_IFMT = 0xF000, // Bits which determine file type
-            S_IFDIR = 0x4000, // Directory
-            S_IFCHR = 0x2000, // Character device
-            S_IFBLK = 0x6000, // Block device
-            S_IFREG = 0x8000, // Regular file
-            S_IFIFO = 0x1000, // FIFO
-            S_IFLNK = 0xA000, // Symbolic link
-            S_IFSOCK = 0xC000, // Socket
-        }
-
-        [StructLayout(LayoutKind.Explicit, Size = 144)]
-        private readonly struct Stat
-        {
-            [FieldOffset(sizeof(ulong) * 3)]
-            public readonly FilePermissions st_mode;
-        }
-
-        [DllImport("libc", SetLastError = true)]
-        private static extern int stat(string path, out Stat stat);
-
-        [DllImport("libc", SetLastError = true)]
-        private static extern int chmod(string path, FilePermissions mode);
-
-        [DllImport("libc", CallingConvention = CallingConvention.Cdecl, SetLastError = true)]
-        private static extern IntPtr strerror(int errno);
-
-        private static void ThrowIf(int i)
-        {
-            if (i == -1)
-            {
-                var errno = Marshal.GetLastWin32Error();
-                throw new Exception(Marshal.PtrToStringAnsi(strerror(errno)));
-            }
-        }
-
-        public static void SetExecute(string path, bool value)
-        {
-            ThrowIf(UnixUtilities.stat(path, out var stat));
-
-            if (stat.st_mode.HasFlag(FilePermissions.EXECUTE) != value)
-            {
-                ThrowIf(chmod(path, value
-                    ? stat.st_mode | FilePermissions.EXECUTE
-                    : stat.st_mode & ~FilePermissions.EXECUTE));
-            }
-        }
-    }
-}