diff --git a/Fuyu.Common/Collections/ThreadDictionary.cs b/Fuyu.Common/Collections/ThreadDictionary.cs
index 423a409d..d3afb00a 100644
--- a/Fuyu.Common/Collections/ThreadDictionary.cs
+++ b/Fuyu.Common/Collections/ThreadDictionary.cs
@@ -1,4 +1,9 @@
 using System.Collections.Generic;
+#if NET9_0_OR_GREATER
+using Lock = System.Threading.Lock;
+#else
+using Lock = object;
+#endif
 
 namespace Fuyu.Common.Collections;
 
@@ -10,18 +15,18 @@ namespace Fuyu.Common.Collections;
 public class ThreadDictionary<T1, T2>
 {
     private readonly Dictionary<T1, T2> _dictionary;
-    private readonly object _lock;
+    private readonly Lock _lock;
 
     public ThreadDictionary()
     {
         _dictionary = new Dictionary<T1, T2>();
-        _lock = new object();
+        _lock = new Lock();
     }
 
     public ThreadDictionary(IDictionary<T1, T2> enumerable)
     {
         _dictionary = new Dictionary<T1, T2>(enumerable);
-        _lock = new object();
+        _lock = new Lock();
     }
 
     public Dictionary<T1, T2> ToDictionary()
diff --git a/Fuyu.Common/Collections/ThreadList.cs b/Fuyu.Common/Collections/ThreadList.cs
index cd3d2bc5..862c9cc8 100644
--- a/Fuyu.Common/Collections/ThreadList.cs
+++ b/Fuyu.Common/Collections/ThreadList.cs
@@ -1,4 +1,9 @@
 using System.Collections.Generic;
+#if NET9_0_OR_GREATER
+using Lock = System.Threading.Lock;
+#else
+using Lock = object;
+#endif
 
 namespace Fuyu.Common.Collections;
 
@@ -11,12 +16,12 @@ namespace Fuyu.Common.Collections;
 public class ThreadList<T>
 {
     private readonly List<T> _list;
-    private readonly object _lock;
+    private readonly Lock _lock;
 
     public ThreadList()
     {
         _list = new List<T>();
-        _lock = new object();
+        _lock = new Lock();
     }
 
     public List<T> ToList()
diff --git a/Fuyu.Common/Collections/ThreadObject.cs b/Fuyu.Common/Collections/ThreadObject.cs
index 7f2690e5..28b02f0a 100644
--- a/Fuyu.Common/Collections/ThreadObject.cs
+++ b/Fuyu.Common/Collections/ThreadObject.cs
@@ -1,14 +1,19 @@
 namespace Fuyu.Common.Collections;
+#if NET9_0_OR_GREATER
+using Lock = System.Threading.Lock;
+#else
+using Lock = object;
+#endif
 
 public class ThreadObject<T>
 {
     private T _object;
-    private readonly object _lock;
+    private readonly Lock _lock;
 
     public ThreadObject(T value)
     {
         _object = value;
-        _lock = new object();
+        _lock = new Lock();
     }
 
     public T Get()
diff --git a/Fuyu.Common/IO/Terminal.cs b/Fuyu.Common/IO/Terminal.cs
index a6c999d2..2133a834 100644
--- a/Fuyu.Common/IO/Terminal.cs
+++ b/Fuyu.Common/IO/Terminal.cs
@@ -1,10 +1,15 @@
 using System;
+#if NET9_0_OR_GREATER
+using Lock = System.Threading.Lock;
+#else
+using Lock = object;
+#endif
 
 namespace Fuyu.Common.IO;
 
 public static class Terminal
 {
-    private static readonly object _lock = new object();
+    private static readonly Lock _lock = new Lock();
     private static string _filepath;
 
     static Terminal()
diff --git a/Fuyu.Common/IO/VFS.cs b/Fuyu.Common/IO/VFS.cs
index ee929714..9214aba7 100644
--- a/Fuyu.Common/IO/VFS.cs
+++ b/Fuyu.Common/IO/VFS.cs
@@ -1,16 +1,21 @@
 using System;
 using System.Collections.Concurrent;
 using System.IO;
+#if NET9_0_OR_GREATER
+using Lock = System.Threading.Lock;
+#else
+using Lock = object;
+#endif
 
 namespace Fuyu.Common.IO;
 
 public static class VFS
 {
-    private static readonly ConcurrentDictionary<string, object> _writeLock;
+    private static readonly ConcurrentDictionary<string, Lock> _writeLock;
 
     static VFS()
     {
-        _writeLock = new ConcurrentDictionary<string, object>();
+        _writeLock = new ConcurrentDictionary<string, Lock>();
     }
 
     public static string GetWorkingDirectory()
@@ -116,7 +121,7 @@ public static void WriteTextFile(string filepath, string text, bool append = fal
         }
 
         // get thread lock
-        _writeLock.TryAdd(filepath, new object());
+        _writeLock.TryAdd(filepath, new Lock());
 
         // write text
         lock (_writeLock[filepath])