diff --git a/CursorLang/Services/SingleInstanceGate.cs b/CursorLang/Services/SingleInstanceGate.cs
index bded8a0..09d29c1 100644
--- a/CursorLang/Services/SingleInstanceGate.cs
+++ b/CursorLang/Services/SingleInstanceGate.cs
@@ -20,13 +20,31 @@ public sealed class SingleInstanceGate : IDisposable
     private const string ActivationEventName = "CursorLang.ActivationRequest";
 
     private readonly Dispatcher _dispatcher = Dispatcher.CurrentDispatcher;
+    private readonly string _mutexName;
+    private readonly string _activationEventName;
 
     private Mutex? _mutex;
     private EventWaitHandle? _activationRequest;
     private RegisteredWaitHandle? _activationWait;
     private bool _isOwner;
 
-    /// <summary>Другой запуск просит показать окно.</summary>
+    public SingleInstanceGate()
+        : this(string.Empty)
+    {
+    }
+
+    /// <summary>
+    /// Adds a distinguishing part to the kernel object names. Needed by the tests:
+    /// otherwise they would share the single-instance slot with the running
+    /// application and get in its way.
+    /// </summary>
+    internal SingleInstanceGate(string nameSuffix)
+    {
+        _mutexName = MutexName + nameSuffix;
+        _activationEventName = ActivationEventName + nameSuffix;
+    }
+
+    /// <summary>Another launch asks for the window to be shown.</summary>
     public event EventHandler? ActivationRequested;
 
     /// <summary>
@@ -35,7 +53,7 @@ public sealed class SingleInstanceGate : IDisposable
     /// </summary>
     public bool TryAcquire()
     {
-        _mutex = new Mutex(initiallyOwned: false, MutexName);
+        _mutex = new Mutex(initiallyOwned: false, _mutexName);
 
         try
         {