diff --git a/fleetd/src/test/java/dev/ltms/fleet/herdr/FakeHerdr.java b/fleetd/src/test/java/dev/ltms/fleet/herdr/FakeHerdr.java
index 2f8b5eb..0cfe48d 100644
--- a/fleetd/src/test/java/dev/ltms/fleet/herdr/FakeHerdr.java
+++ b/fleetd/src/test/java/dev/ltms/fleet/herdr/FakeHerdr.java
@@ -7,6 +7,7 @@ import java.util.ArrayList;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.CopyOnWriteArrayList;
 
 /**
@@ -41,7 +42,7 @@ public final class FakeHerdr implements HerdrClient {
     private int agentPaneBusyFor = 0;
     private int workerTabPaneCount = 1;
     private String paneCloseErrorCode = null;
-    private final Map<String, String> paneCloseErrorCodeFor = new java.util.concurrent.ConcurrentHashMap<>();
+    private final Map<String, String> paneCloseErrorCodeFor = new ConcurrentHashMap<>();
     private String agentSendErrorCode = null;
     private boolean noPanes = false;
     private volatile String agentStatus = "idle"; // steady-state agent.get status
@@ -373,7 +374,7 @@ public final class FakeHerdr implements HerdrClient {
                                   "foreground_processes":[]}}""");
                 }
                 case "pane.close" -> {
-                    Object paneIdParam = params instanceof java.util.Map<?, ?> m ? m.get("pane_id") : null;
+                    Object paneIdParam = params instanceof Map<?, ?> m ? m.get("pane_id") : null;
                     String perPaneCode = paneIdParam == null ? null
                             : paneCloseErrorCodeFor.get(String.valueOf(paneIdParam));
                     String code = perPaneCode != null ? perPaneCode : paneCloseErrorCode;