diff --git a/src/LLTSharp/ITemplate.cs b/src/LLTSharp/ITemplate.cs
index 60acee6..5a2eb51 100644
--- a/src/LLTSharp/ITemplate.cs
+++ b/src/LLTSharp/ITemplate.cs
@@ -12,8 +12,9 @@ public interface ITemplate : IMetadataProvider
 		/// Renders the template with the given context.
 		/// </summary>
 		/// <param name="context">The context to use for rendering the template. Can be null.</param>
+		/// <param name="functions">Optional set of functions to use during rendering. Can be null.</param>
 		/// <returns>The result of rendering the template.</returns>
-		object Render(object? context = null);
+		object Render(object? context = null, TemplateFunctionSet? functions = null);
 	}
 	
 	/// <summary>
@@ -22,8 +23,8 @@ public interface ITemplate : IMetadataProvider
 	/// <typeparam name="TResult">The type of result produced by the template.</typeparam>
 	public interface ITemplate<TResult> : ITemplate
 	{
-		/// <inheritdoc cref="ITemplate.Render(object?)"/>
-		new TResult Render(object? context = null);
+		/// <inheritdoc cref="ITemplate.Render(object?, TemplateFunctionSet?)"/>
+		new TResult Render(object? context = null, TemplateFunctionSet? functions = null);
 	}
 
 	/// <summary>
diff --git a/src/LLTSharp/MessagesTemplate.cs b/src/LLTSharp/MessagesTemplate.cs
index f038c6e..c592e59 100644
--- a/src/LLTSharp/MessagesTemplate.cs
+++ b/src/LLTSharp/MessagesTemplate.cs
@@ -33,20 +33,15 @@ public MessagesTemplate(MessagesTemplateNode mainNode, IMetadataCollection metad
 			LocalLibrary = localLibrary ?? throw new ArgumentNullException(nameof(localLibrary));
 		}
 
-		/// <summary>
-		/// Renders the messages template using the provided data accessor.
-		/// </summary>
-		/// <param name="context">The context accessor to use for rendering.</param>
-		/// <returns>The rendered prompt as a collection of messages.</returns>
-		public IEnumerable<Message> Render(object? context = null)
+		public IEnumerable<Message> Render(object? context = null, TemplateFunctionSet? functions = null)
 		{
-			var ctx = new TemplateContextAccessor(TemplateDataAccessor.Create(context), Metadata, library: LocalLibrary);
+			var ctx = new TemplateContextAccessor(TemplateDataAccessor.Create(context), Metadata, functions: functions, library: LocalLibrary);
 			return _node.Render(ctx);
 		}
 
-		object ITemplate.Render(object? context)
+		object ITemplate.Render(object? context, TemplateFunctionSet? functions)
 		{
-			var ctx = new TemplateContextAccessor(TemplateDataAccessor.Create(context), Metadata, library: LocalLibrary);
+			var ctx = new TemplateContextAccessor(TemplateDataAccessor.Create(context), Metadata, functions: functions, library: LocalLibrary);
 			return _node.Render(ctx);
 		}
 	}
diff --git a/src/LLTSharp/PlaintextTemplate.cs b/src/LLTSharp/PlaintextTemplate.cs
index 163b9ab..c23f05d 100644
--- a/src/LLTSharp/PlaintextTemplate.cs
+++ b/src/LLTSharp/PlaintextTemplate.cs
@@ -49,14 +49,14 @@ public PlaintextTemplate(string content, IMetadataCollection metadata)
 			Metadata = new MetadataCollection(metadata) ?? throw new ArgumentNullException(nameof(metadata));
 		}
 
-		public string Render(object? context = null)
+		public string Render(object? context = null, TemplateFunctionSet? functions = null)
 		{
 			return Content;
 		}
 
-		object ITemplate.Render(object? context)
+		object ITemplate.Render(object? context, TemplateFunctionSet? functions)
 		{
-			return Render(context);
+			return Render(context, functions);
 		}
 	}
 }
\ No newline at end of file
diff --git a/src/LLTSharp/TextTemplate.cs b/src/LLTSharp/TextTemplate.cs
index 87f8393..f8ecee4 100644
--- a/src/LLTSharp/TextTemplate.cs
+++ b/src/LLTSharp/TextTemplate.cs
@@ -35,20 +35,15 @@ public TextTemplate(TextTemplateNode mainNode, IMetadataCollection metadata, Tem
 			LocalLibrary = localLibrary ?? throw new ArgumentNullException(nameof(localLibrary));
 		}
 
-		/// <summary>
-		/// Renders the text template using the provided data accessor.
-		/// </summary>
-		/// <param name="context">The context accessor to use for rendering.</param>
-		/// <returns>The rendered text as a string.</returns>
-		public string Render(object? context = null)
+		public string Render(object? context = null, TemplateFunctionSet? functions = null)
 		{
-			var ctx = new TemplateContextAccessor(TemplateDataAccessor.Create(context), Metadata, library: LocalLibrary);
+			var ctx = new TemplateContextAccessor(TemplateDataAccessor.Create(context), Metadata, functions: functions, library: LocalLibrary);
 			return _node.Render(ctx);
 		}
 
-		object ITemplate.Render(object? context)
+		object ITemplate.Render(object? context, TemplateFunctionSet? functions)
 		{
-			var ctx = new TemplateContextAccessor(TemplateDataAccessor.Create(context), Metadata, library: LocalLibrary);
+			var ctx = new TemplateContextAccessor(TemplateDataAccessor.Create(context), Metadata, functions: functions, library: LocalLibrary);
 			return _node.Render(ctx);
 		}
 	}