diff --git a/connector/src/main/java/org/geysermc/connector/network/session/cache/InventoryCache.java b/connector/src/main/java/org/geysermc/connector/network/session/cache/InventoryCache.java
index 8734c710..032f6402 100644
--- a/connector/src/main/java/org/geysermc/connector/network/session/cache/InventoryCache.java
+++ b/connector/src/main/java/org/geysermc/connector/network/session/cache/InventoryCache.java
@@ -25,14 +25,13 @@
 
 package org.geysermc.connector.network.session.cache;
 
+import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
+import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import lombok.Getter;
 import lombok.Setter;
 import org.geysermc.connector.inventory.Inventory;
 import org.geysermc.connector.network.session.GeyserSession;
 
-import java.util.HashMap;
-import java.util.Map;
-
 public class InventoryCache {
 
     private GeyserSession session;
@@ -42,7 +41,7 @@ public class InventoryCache {
     private Inventory openInventory;
 
     @Getter
-    private Map<Integer, Inventory> inventories = new HashMap<Integer, Inventory>();
+    private Int2ObjectMap<Inventory> inventories = new Int2ObjectOpenHashMap<>();
 
     public InventoryCache(GeyserSession session) {
         this.session = session;
diff --git a/connector/src/main/java/org/geysermc/connector/network/translators/java/JavaServerDeclareCommandsTranslator.java b/connector/src/main/java/org/geysermc/connector/network/translators/java/JavaServerDeclareCommandsTranslator.java
index edc20a64..d57b8948 100644
--- a/connector/src/main/java/org/geysermc/connector/network/translators/java/JavaServerDeclareCommandsTranslator.java
+++ b/connector/src/main/java/org/geysermc/connector/network/translators/java/JavaServerDeclareCommandsTranslator.java
@@ -32,6 +32,8 @@ import com.nukkitx.protocol.bedrock.data.CommandData;
 import com.nukkitx.protocol.bedrock.data.CommandEnumData;
 import com.nukkitx.protocol.bedrock.data.CommandParamData;
 import com.nukkitx.protocol.bedrock.packet.AvailableCommandsPacket;
+import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
+import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import lombok.Getter;
 import org.geysermc.connector.GeyserConnector;
 import org.geysermc.connector.network.session.GeyserSession;
@@ -45,8 +47,8 @@ public class JavaServerDeclareCommandsTranslator extends PacketTranslator<Server
     @Override
     public void translate(ServerDeclareCommandsPacket packet, GeyserSession session) {
         List<CommandData> commandData = new ArrayList<>();
-        Map<Integer, String> commands = new HashMap<>();
-        Map<Integer, List<CommandNode>> commandArgs = new HashMap<>();
+        Int2ObjectMap<String> commands = new Int2ObjectOpenHashMap<>();
+        Int2ObjectMap<List<CommandNode>> commandArgs = new Int2ObjectOpenHashMap<>();
 
         // Get the first node, it should be a root node
         CommandNode rootNode = packet.getNodes()[packet.getFirstNodeIndex()];