diff --git a/aidge_core/export_utils/code_generation.py b/aidge_core/export_utils/code_generation.py
index a02fc0966702cec7a2cbe33f8411bb71e3035e90..29b24bb82314cdd85db78c71b98bbead68a0b855 100644
--- a/aidge_core/export_utils/code_generation.py
+++ b/aidge_core/export_utils/code_generation.py
@@ -1,5 +1,5 @@
 from pathlib import Path
-from jinja2 import Environment, FileSystemLoader
+from jinja2 import Environment, FileSystemLoader, StrictUndefined
 from typing import Union
 
 
@@ -21,13 +21,9 @@ def generate_file(file_path: Union[Path, str], template_path: Union[Path, str],
     # Make dir
     file_path.parent.mkdir(parents=True, exist_ok=True)
 
-    # Select template
-    template = Environment(loader=FileSystemLoader(
-        template_path.parent)).get_template(template_path.name)
-
     # Generate file
     with open(file_path, mode="w", encoding="utf-8") as file:
-        file.write(template.render(kwargs))
+        file.write(generate_str(template_path, **kwargs))
 
 
 def generate_str(template_path: Union[Path, str], **kwargs) -> str:
@@ -43,4 +39,4 @@ def generate_str(template_path: Union[Path, str], **kwargs) -> str:
     if isinstance(template_path, str):
         template_path = Path(template_path)
     return Environment(loader=FileSystemLoader(
-        template_path.parent)).get_template(template_path.name).render(kwargs)
+        template_path.parent), undefined=StrictUndefined).get_template(template_path.name).render(kwargs)