diff --git a/build.gradle b/build.gradle
index 7b49f6c..214fd6a 100644
--- a/build.gradle
+++ b/build.gradle
@@ -47,7 +47,7 @@ allprojects {
     }
 
     dependencies {
-        compileOnly 'com.willfp:eco:6.37.1'
+        compileOnly 'com.willfp:eco:6.42.0'
         implementation 'com.willfp:libreforge:3.105.0'
         implementation 'org.joml:joml:1.10.4'
 
diff --git a/eco-core/core-plugin/src/main/kotlin/com/willfp/ecopets/pets/PetLevelGUI.kt b/eco-core/core-plugin/src/main/kotlin/com/willfp/ecopets/pets/PetLevelGUI.kt
index 5335930..8097d04 100644
--- a/eco-core/core-plugin/src/main/kotlin/com/willfp/ecopets/pets/PetLevelGUI.kt
+++ b/eco-core/core-plugin/src/main/kotlin/com/willfp/ecopets/pets/PetLevelGUI.kt
@@ -178,6 +178,14 @@ class PetLevelGUI(
                     }
                 }
             )
+
+            for (config in plugin.configYml.getSubsections("level-gui.custom-slots")) {
+                setSlot(
+                    config.getInt("row"),
+                    config.getInt("column"),
+                    ConfigSlot(config)
+                )
+            }
         }
     }
 
diff --git a/eco-core/core-plugin/src/main/kotlin/com/willfp/ecopets/pets/PetsGUI.kt b/eco-core/core-plugin/src/main/kotlin/com/willfp/ecopets/pets/PetsGUI.kt
index 845fe1f..2c9ecdf 100644
--- a/eco-core/core-plugin/src/main/kotlin/com/willfp/ecopets/pets/PetsGUI.kt
+++ b/eco-core/core-plugin/src/main/kotlin/com/willfp/ecopets/pets/PetsGUI.kt
@@ -200,6 +200,14 @@ object PetsGUI {
                     }
                 }
             )
+
+            for (config in plugin.configYml.getSubsections("gui.custom-slots")) {
+                setSlot(
+                    config.getInt("row"),
+                    config.getInt("column"),
+                    ConfigSlot(config)
+                )
+            }
         }
     }
 
diff --git a/eco-core/core-plugin/src/main/resources/config.yml b/eco-core/core-plugin/src/main/resources/config.yml
index 3fb4be7..8e2fc7f 100644
--- a/eco-core/core-plugin/src/main/resources/config.yml
+++ b/eco-core/core-plugin/src/main/resources/config.yml
@@ -116,6 +116,9 @@ gui:
       row: 6
       column: 2
 
+  # Custom GUI slots; see here for a how-to: https://plugins.auxilor.io/all-plugins/custom-gui-slots
+  custom-slots: [ ]
+
 level-gui:
   rows: 6
 
@@ -210,6 +213,9 @@ level-gui:
       row: 6
       column: 5
 
+  # Custom GUI slots; see here for a how-to: https://plugins.auxilor.io/all-plugins/custom-gui-slots
+  custom-slots: [ ]
+
 pet-entity:
   name: "%player%&f's %pet%&f (Lvl. %level%)"
 
diff --git a/gradle.properties b/gradle.properties
index 4e898cb..392c004 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,4 +1,4 @@
 #libreforge-updater
 #Mon Sep 26 18:28:24 BST 2022
-version=1.42.0
+version=1.43.0
 plugin-name=EcoPets