diff --git a/eco-api/src/main/java/com/willfp/eco/core/gui/GUIFactory.java b/eco-api/src/main/java/com/willfp/eco/core/gui/GUIFactory.java
index 59e9591d..d13c794e 100644
--- a/eco-api/src/main/java/com/willfp/eco/core/gui/GUIFactory.java
+++ b/eco-api/src/main/java/com/willfp/eco/core/gui/GUIFactory.java
@@ -1,7 +1,7 @@
 package com.willfp.eco.core.gui;
 
-import com.willfp.eco.core.gui.menu.Menu;
-import com.willfp.eco.core.gui.slot.Slot;
+import com.willfp.eco.core.gui.menu.MenuBuilder;
+import com.willfp.eco.core.gui.slot.SlotBuilder;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -15,7 +15,7 @@ public interface GUIFactory {
      * @param provider The provider.
      * @return The builder.
      */
-    Slot.Builder createSlotBuilder(@NotNull Function<Player, ItemStack> provider);
+    SlotBuilder createSlotBuilder(@NotNull Function<Player, ItemStack> provider);
 
     /**
      * Create menu builder.
@@ -23,5 +23,5 @@ public interface GUIFactory {
      * @param rows The amount of rows.
      * @return The builder.
      */
-    Menu.Builder createMenuBuilder(int rows);
+    MenuBuilder createMenuBuilder(int rows);
 }
diff --git a/eco-api/src/main/java/com/willfp/eco/core/gui/menu/Menu.java b/eco-api/src/main/java/com/willfp/eco/core/gui/menu/Menu.java
index 810f493d..18ef119b 100644
--- a/eco-api/src/main/java/com/willfp/eco/core/gui/menu/Menu.java
+++ b/eco-api/src/main/java/com/willfp/eco/core/gui/menu/Menu.java
@@ -1,15 +1,11 @@
 package com.willfp.eco.core.gui.menu;
 
 import com.willfp.eco.core.Eco;
-import com.willfp.eco.core.gui.slot.FillerMask;
 import com.willfp.eco.core.gui.slot.Slot;
 import org.bukkit.entity.Player;
-import org.bukkit.event.inventory.InventoryCloseEvent;
 import org.bukkit.inventory.Inventory;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.function.Consumer;
-
 public interface Menu {
     /**
      * Get the amount of rows.
@@ -49,21 +45,7 @@ public interface Menu {
      * @param rows The rows.
      * @return The builder.
      */
-    static Builder builder(final int rows) {
+    static MenuBuilder builder(final int rows) {
         return Eco.getHandler().getGUIFactory().createMenuBuilder(rows);
     }
-
-    interface Builder {
-        Builder setTitle(@NotNull String title);
-
-        Builder setSlot(int row,
-                        int column,
-                        @NotNull Slot slot);
-
-        Builder setMask(@NotNull FillerMask mask);
-
-        Builder onClose(@NotNull Consumer<InventoryCloseEvent> action);
-
-        Menu build();
-    }
 }
diff --git a/eco-api/src/main/java/com/willfp/eco/core/gui/menu/MenuBuilder.java b/eco-api/src/main/java/com/willfp/eco/core/gui/menu/MenuBuilder.java
new file mode 100644
index 00000000..b019df51
--- /dev/null
+++ b/eco-api/src/main/java/com/willfp/eco/core/gui/menu/MenuBuilder.java
@@ -0,0 +1,22 @@
+package com.willfp.eco.core.gui.menu;
+
+import com.willfp.eco.core.gui.slot.FillerMask;
+import com.willfp.eco.core.gui.slot.Slot;
+import org.bukkit.event.inventory.InventoryCloseEvent;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.function.Consumer;
+
+public interface MenuBuilder {
+    MenuBuilder setTitle(@NotNull String title);
+
+    MenuBuilder setSlot(int row,
+                         int column,
+                         @NotNull Slot slot);
+
+    MenuBuilder setMask(@NotNull FillerMask mask);
+
+    MenuBuilder onClose(@NotNull Consumer<InventoryCloseEvent> action);
+
+    Menu build();
+}
diff --git a/eco-api/src/main/java/com/willfp/eco/core/gui/slot/Slot.java b/eco-api/src/main/java/com/willfp/eco/core/gui/slot/Slot.java
index 76f45567..c3777d8c 100644
--- a/eco-api/src/main/java/com/willfp/eco/core/gui/slot/Slot.java
+++ b/eco-api/src/main/java/com/willfp/eco/core/gui/slot/Slot.java
@@ -2,11 +2,9 @@ package com.willfp.eco.core.gui.slot;
 
 import com.willfp.eco.core.Eco;
 import org.bukkit.entity.Player;
-import org.bukkit.event.inventory.InventoryClickEvent;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.function.BiConsumer;
 import java.util.function.Function;
 
 public interface Slot {
@@ -24,7 +22,7 @@ public interface Slot {
      * @param itemStack The ItemStack.
      * @return The builder.
      */
-    static Builder builder(@NotNull final ItemStack itemStack) {
+    static SlotBuilder builder(@NotNull final ItemStack itemStack) {
         return Eco.getHandler().getGUIFactory().createSlotBuilder(player -> itemStack);
     }
 
@@ -34,21 +32,7 @@ public interface Slot {
      * @param provider The provider.
      * @return The builder.
      */
-    static Builder builder(@NotNull final Function<Player, ItemStack> provider) {
+    static SlotBuilder builder(@NotNull final Function<Player, ItemStack> provider) {
         return Eco.getHandler().getGUIFactory().createSlotBuilder(provider);
     }
-
-    interface Builder {
-        Builder onLeftClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
-
-        Builder onRightClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
-
-        Builder onShiftLeftClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
-
-        Builder onShiftRightClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
-
-        Builder onMiddleClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
-
-        Slot build();
-    }
 }
diff --git a/eco-api/src/main/java/com/willfp/eco/core/gui/slot/SlotBuilder.java b/eco-api/src/main/java/com/willfp/eco/core/gui/slot/SlotBuilder.java
new file mode 100644
index 00000000..87e249f2
--- /dev/null
+++ b/eco-api/src/main/java/com/willfp/eco/core/gui/slot/SlotBuilder.java
@@ -0,0 +1,20 @@
+package com.willfp.eco.core.gui.slot;
+
+import org.bukkit.event.inventory.InventoryClickEvent;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.function.BiConsumer;
+
+public interface SlotBuilder {
+    SlotBuilder onLeftClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+
+    SlotBuilder onRightClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+
+    SlotBuilder onShiftLeftClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+
+    SlotBuilder onShiftRightClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+
+    SlotBuilder onMiddleClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+
+    Slot build();
+}
diff --git a/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/EcoGUIFactory.java b/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/EcoGUIFactory.java
index 7c0e789a..800940a4 100644
--- a/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/EcoGUIFactory.java
+++ b/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/EcoGUIFactory.java
@@ -1,8 +1,8 @@
 package com.willfp.eco.internal.gui;
 
 import com.willfp.eco.core.gui.GUIFactory;
-import com.willfp.eco.core.gui.menu.Menu;
-import com.willfp.eco.core.gui.slot.Slot;
+import com.willfp.eco.core.gui.menu.MenuBuilder;
+import com.willfp.eco.core.gui.slot.SlotBuilder;
 import com.willfp.eco.internal.gui.menu.EcoMenuBuilder;
 import com.willfp.eco.internal.gui.slot.EcoSlotBuilder;
 import org.bukkit.entity.Player;
@@ -13,12 +13,12 @@ import java.util.function.Function;
 
 public class EcoGUIFactory implements GUIFactory {
     @Override
-    public Slot.Builder createSlotBuilder(@NotNull final Function<Player, ItemStack> provider) {
+    public SlotBuilder createSlotBuilder(@NotNull final Function<Player, ItemStack> provider) {
         return new EcoSlotBuilder(provider);
     }
 
     @Override
-    public Menu.Builder createMenuBuilder(final int rows) {
+    public MenuBuilder createMenuBuilder(final int rows) {
         return new EcoMenuBuilder(rows);
     }
 }
diff --git a/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/menu/EcoMenuBuilder.java b/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/menu/EcoMenuBuilder.java
index 569a9bd3..4b19f426 100644
--- a/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/menu/EcoMenuBuilder.java
+++ b/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/menu/EcoMenuBuilder.java
@@ -1,6 +1,7 @@
 package com.willfp.eco.internal.gui.menu;
 
 import com.willfp.eco.core.gui.menu.Menu;
+import com.willfp.eco.core.gui.menu.MenuBuilder;
 import com.willfp.eco.core.gui.slot.FillerMask;
 import com.willfp.eco.core.gui.slot.Slot;
 import com.willfp.eco.internal.gui.slot.EcoFillerSlot;
@@ -14,7 +15,7 @@ import org.jetbrains.annotations.NotNull;
 import java.util.List;
 import java.util.function.Consumer;
 
-public class EcoMenuBuilder implements Menu.Builder {
+public class EcoMenuBuilder implements MenuBuilder {
 
     /**
      * The amount of rows.
@@ -49,13 +50,13 @@ public class EcoMenuBuilder implements Menu.Builder {
     }
 
     @Override
-    public Menu.Builder setTitle(@NotNull final String title) {
+    public MenuBuilder setTitle(@NotNull final String title) {
         this.title = StringUtils.translate(title);
         return this;
     }
 
     @Override
-    public Menu.Builder setSlot(final int row,
+    public MenuBuilder setSlot(final int row,
                                 final int column,
                                 @NotNull final Slot slot) {
         if (row < 1 || row > this.rows) {
@@ -71,13 +72,13 @@ public class EcoMenuBuilder implements Menu.Builder {
     }
 
     @Override
-    public Menu.Builder setMask(@NotNull final FillerMask mask) {
+    public MenuBuilder setMask(@NotNull final FillerMask mask) {
         this.maskSlots = mask.getMask();
         return this;
     }
 
     @Override
-    public Menu.Builder onClose(@NotNull final Consumer<InventoryCloseEvent> action) {
+    public MenuBuilder onClose(@NotNull final Consumer<InventoryCloseEvent> action) {
         this.onClose = action;
         return this;
     }
diff --git a/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/slot/EcoSlotBuilder.java b/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/slot/EcoSlotBuilder.java
index 6d8c5084..a53332c8 100644
--- a/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/slot/EcoSlotBuilder.java
+++ b/eco-core/core-backend/src/main/java/com/willfp/eco/internal/gui/slot/EcoSlotBuilder.java
@@ -1,6 +1,7 @@
 package com.willfp.eco.internal.gui.slot;
 
 import com.willfp.eco.core.gui.slot.Slot;
+import com.willfp.eco.core.gui.slot.SlotBuilder;
 import org.bukkit.entity.Player;
 import org.bukkit.event.inventory.InventoryClickEvent;
 import org.bukkit.inventory.ItemStack;
@@ -9,7 +10,7 @@ import org.jetbrains.annotations.NotNull;
 import java.util.function.BiConsumer;
 import java.util.function.Function;
 
-public class EcoSlotBuilder implements Slot.Builder {
+public class EcoSlotBuilder implements SlotBuilder {
     /**
      * Provider.
      */
@@ -44,27 +45,27 @@ public class EcoSlotBuilder implements Slot.Builder {
         this.provider = provider;
     }
 
-    public Slot.Builder onLeftClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
+    public SlotBuilder onLeftClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
         this.onLeftClick = action;
         return this;
     }
 
-    public Slot.Builder onRightClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
+    public SlotBuilder onRightClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
         this.onRightClick = action;
         return this;
     }
 
-    public Slot.Builder onShiftLeftClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
+    public SlotBuilder onShiftLeftClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
         this.onShiftLeftClick = action;
         return this;
     }
 
-    public Slot.Builder onShiftRightClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
+    public SlotBuilder onShiftRightClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
         this.onShiftRightClick = action;
         return this;
     }
 
-    public Slot.Builder onMiddleClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
+    public SlotBuilder onMiddleClick(@NotNull final BiConsumer<InventoryClickEvent, Slot> action) {
         this.onMiddleClick = action;
         return this;
     }