diff --git a/src/Hydrogen/ObjectSpaces/Builder/ObjectSpaceBuilder.cs b/src/Hydrogen/ObjectSpaces/Builder/ObjectSpaceBuilder.cs
index 2ff2eeab..d94fa7b2 100644
--- a/src/Hydrogen/ObjectSpaces/Builder/ObjectSpaceBuilder.cs
+++ b/src/Hydrogen/ObjectSpaces/Builder/ObjectSpaceBuilder.cs
@@ -141,6 +141,10 @@ public ObjectSpaceBuilder UsingSerializerFactory(SerializerFactory factory) {
 		return this;
 	}
 
+	public bool ContainsSerializer<TItem>() => ContainsSerializer(typeof(TItem));
+
+	public bool ContainsSerializer(Type type) => _serializerFactory.ContainsSerializer(type);
+
 	public ObjectSpaceBuilder UsingSerializer<TItem, TItemSerializer>() where TItemSerializer : IItemSerializer<TItem>, new() {
 		Guard.Against(_usingCustomSerializerFactory, ErrMsgUsingSerializer);
 		_specifiedCustomSerializer = true;
@@ -155,6 +159,15 @@ public ObjectSpaceBuilder UsingSerializer<TItem>(IItemSerializer<TItem> serializ
 		return this;
 	}
 
+	public ObjectSpaceBuilder MakeSerializer<TItem>() => MakeSerializer(typeof(TItem));
+
+	public ObjectSpaceBuilder MakeSerializer(Type type) {
+		Guard.Ensure(!_serializerFactory.ContainsSerializer(type), $"Serializer for type {type.ToStringCS()} has already been registered.");
+		_specifiedCustomSerializer = true;
+		_serializerFactory.RegisterAutoBuild(type);
+		return this;
+	}
+
 	public ObjectSpaceBuilder UsingComparerFactory(ComparerFactory factory) {
 		Guard.ArgumentNotNull(factory, nameof(factory));
 		Guard.Against(_specifiedCustomComparer, ErrMsgUseComparerFactory);
diff --git a/src/Hydrogen/ObjectSpaces/Builder/ObjectSpaceDimensionBuilder.cs b/src/Hydrogen/ObjectSpaces/Builder/ObjectSpaceDimensionBuilder.cs
index 2c821de5..3e972acf 100644
--- a/src/Hydrogen/ObjectSpaces/Builder/ObjectSpaceDimensionBuilder.cs
+++ b/src/Hydrogen/ObjectSpaces/Builder/ObjectSpaceDimensionBuilder.cs
@@ -42,6 +42,11 @@ public ObjectSpaceDimensionBuilder<T> UsingSerializer(IItemSerializer<T> seriali
 		return this;
 	}
 
+	public ObjectSpaceDimensionBuilder<T> MakeSerializer() {
+		_parent.MakeSerializer<T>();
+		return this;
+	}
+
 	public ObjectSpaceDimensionBuilder<T> UsingComparer<TComparer>() where TComparer : IComparer<T>, new() {
 		_parent.UsingComparer<T, TComparer>();
 		return this;
@@ -161,6 +166,8 @@ public ObjectSpaceDimensionBuilder<T> OptimizeAssumingAverageItemSize(int bytes)
 	}
 
 	public ObjectSpaceBuilder Done() {
+		if (!_parent.ContainsSerializer(typeof(T))) 
+			MakeSerializer();
 		return _parent;
 	}