diff --git a/core/src/main/java/cc/carm/lib/configuration/core/builder/map/ConfigMapBuilder.java b/core/src/main/java/cc/carm/lib/configuration/core/builder/map/ConfigMapBuilder.java
index 74f5219..ecfa675 100644
--- a/core/src/main/java/cc/carm/lib/configuration/core/builder/map/ConfigMapBuilder.java
+++ b/core/src/main/java/cc/carm/lib/configuration/core/builder/map/ConfigMapBuilder.java
@@ -8,12 +8,12 @@ import java.util.function.Supplier;
 
 public class ConfigMapBuilder<M extends Map<K, V>, K, V> {
 
-    protected final @NotNull Supplier<@NotNull M> supplier;
+    protected final @NotNull Supplier<? extends M> supplier;
 
     protected final @NotNull Class<K> keyClass;
     protected final @NotNull Class<V> valueClass;
 
-    public ConfigMapBuilder(@NotNull Supplier<@NotNull M> supplier, @NotNull Class<K> keyClass, @NotNull Class<V> valueClass) {
+    public ConfigMapBuilder(@NotNull Supplier<? extends M> supplier, @NotNull Class<K> keyClass, @NotNull Class<V> valueClass) {
         this.supplier = supplier;
         this.keyClass = keyClass;
         this.valueClass = valueClass;
diff --git a/core/src/main/java/cc/carm/lib/configuration/core/builder/map/ConfigMapCreator.java b/core/src/main/java/cc/carm/lib/configuration/core/builder/map/ConfigMapCreator.java
index 6e66efe..4b92a5b 100644
--- a/core/src/main/java/cc/carm/lib/configuration/core/builder/map/ConfigMapCreator.java
+++ b/core/src/main/java/cc/carm/lib/configuration/core/builder/map/ConfigMapCreator.java
@@ -2,10 +2,7 @@ package cc.carm.lib.configuration.core.builder.map;
 
 import org.jetbrains.annotations.NotNull;
 
-import java.util.HashMap;
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.TreeMap;
+import java.util.*;
 import java.util.function.Supplier;
 
 public class ConfigMapCreator<K, V> {
@@ -18,7 +15,7 @@ public class ConfigMapCreator<K, V> {
         this.valueClass = valueClass;
     }
 
-    public <M extends Map<K, V>> @NotNull ConfigMapBuilder<M, K, V> asMap(Supplier<M> mapSuppler) {
+    public <M extends Map<K, V>> @NotNull ConfigMapBuilder<M, K, V> asMap(Supplier<? extends M> mapSuppler) {
         return new ConfigMapBuilder<>(mapSuppler, keyClass, valueClass);
     }
 
@@ -34,4 +31,8 @@ public class ConfigMapCreator<K, V> {
         return asMap(TreeMap::new);
     }
 
+    public @NotNull ConfigMapBuilder<TreeMap<K, V>, K, V> asTreeMap(@NotNull Comparator<? super K> comparator) {
+        return asMap(() -> new TreeMap<>(comparator));
+    }
+
 }
diff --git a/core/src/main/java/cc/carm/lib/configuration/core/builder/map/SectionMapBuilder.java b/core/src/main/java/cc/carm/lib/configuration/core/builder/map/SectionMapBuilder.java
index 13e9764..e94fdbe 100644
--- a/core/src/main/java/cc/carm/lib/configuration/core/builder/map/SectionMapBuilder.java
+++ b/core/src/main/java/cc/carm/lib/configuration/core/builder/map/SectionMapBuilder.java
@@ -15,7 +15,7 @@ import java.util.function.Supplier;
 
 public class SectionMapBuilder<M extends Map<K, V>, K, V> extends CommonConfigBuilder<M, SectionMapBuilder<M, K, V>> {
 
-    protected final @NotNull Supplier<@NotNull M> supplier;
+    protected final @NotNull Supplier<? extends M> supplier;
 
     protected final @NotNull Class<K> keyClass;
     protected @NotNull ConfigDataFunction<String, K> keyParser;
@@ -26,7 +26,7 @@ public class SectionMapBuilder<M extends Map<K, V>, K, V> extends CommonConfigBu
     protected @NotNull ConfigDataFunction<K, String> keySerializer;
     protected @NotNull ConfigDataFunction<V, ? extends Map<String, Object>> valueSerializer;
 
-    public SectionMapBuilder(@NotNull Supplier<@NotNull M> supplier,
+    public SectionMapBuilder(@NotNull Supplier<? extends M> supplier,
                              @NotNull Class<K> keyClass, @NotNull ConfigDataFunction<String, K> keyParser,
                              @NotNull Class<V> valueClass, @NotNull ConfigDataFunction<ConfigurationWrapper<?>, V> valueParser,
                              @NotNull ConfigDataFunction<K, String> keySerializer,
diff --git a/core/src/main/java/cc/carm/lib/configuration/core/builder/map/SourceMapBuilder.java b/core/src/main/java/cc/carm/lib/configuration/core/builder/map/SourceMapBuilder.java
index f70330c..90d6636 100644
--- a/core/src/main/java/cc/carm/lib/configuration/core/builder/map/SourceMapBuilder.java
+++ b/core/src/main/java/cc/carm/lib/configuration/core/builder/map/SourceMapBuilder.java
@@ -12,7 +12,7 @@ import java.util.function.Supplier;
 
 public class SourceMapBuilder<M extends Map<K, V>, S, K, V> extends CommonConfigBuilder<M, SourceMapBuilder<M, S, K, V>> {
 
-    protected final @NotNull Supplier<@NotNull M> supplier;
+    protected final @NotNull Supplier<? extends M> supplier;
 
     protected final @NotNull Class<K> keyClass;
     protected @NotNull ConfigDataFunction<String, K> keyParser;
@@ -27,7 +27,7 @@ public class SourceMapBuilder<M extends Map<K, V>, S, K, V> extends CommonConfig
     protected @NotNull ConfigDataFunction<V, S> valueSerializer;
     protected @NotNull ConfigDataFunction<S, Object> sourceSerializer;
 
-    public SourceMapBuilder(@NotNull Supplier<@NotNull M> supplier,
+    public SourceMapBuilder(@NotNull Supplier<? extends M> supplier,
                             @NotNull Class<K> keyClass, @NotNull ConfigDataFunction<String, K> keyParser,
                             @NotNull Class<S> sourceClass, @NotNull ConfigDataFunction<Object, S> sourceParser,
                             @NotNull Class<V> valueClass, @NotNull ConfigDataFunction<S, V> valueParser,