diff --git a/nanochat/logger.py b/nanochat/logger.py
new file mode 100644
index 0000000..bde63ea
--- /dev/null
+++ b/nanochat/logger.py
@@ -0,0 +1,26 @@
+from functools import wraps
+
+from loguru import logger
+
+
+def log(func):
+    """A decorator to log function calls, arguments, and return values."""
+
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        # Log function start and arguments
+        logger.info(f"Function '{func.__name__}' | args: {args} | kwargs: {kwargs}")
+        try:
+            # Call the original function
+            result = func(*args, **kwargs)
+            # Log function end and return value
+            logger.info(f"Function '{func.__name__}' finished, returned: {result}")
+            return result
+        except Exception as e:
+            # Log any exceptions
+            logger.error(
+                f"Function '{func.__name__}' raised an exception: {e}", exc_info=True
+            )
+            raise
+
+    return wrapper