diff --git a/khaosz/config/train_config.py b/khaosz/config/train_config.py
index cb4a8ac..44f20c4 100644
--- a/khaosz/config/train_config.py
+++ b/khaosz/config/train_config.py
@@ -105,6 +105,11 @@ class TrainConfig:
         default=None,
         metadata={"help": "Parallel function for training."}
     )
+    state_dict_wrapper: Optional[Callable] = field(
+         default=None,
+         metadata={"help": "Parallel function for state  dict saving."}
+    )
+    
     optimizer_factory: Optional[Callable[[nn.Module], Optimizer]] = field(
         default=None,
         metadata={"help": "Optimizer factory for training."}
diff --git a/khaosz/trainer/train_callback.py b/khaosz/trainer/train_callback.py
index da9cd13..b1c0a9d 100644
--- a/khaosz/trainer/train_callback.py
+++ b/khaosz/trainer/train_callback.py
@@ -1,12 +1,13 @@
 import os
 import json
 import time
+import torch.nn as nn
 
 from pathlib import Path
 from tqdm import tqdm
 from torch.nn.utils import clip_grad_norm_
 from torch.optim.lr_scheduler import LRScheduler
-from typing import List, Literal, Optional, Protocol, TYPE_CHECKING
+from typing import Callable, List, Optional, Protocol, TYPE_CHECKING
 
 from khaosz.parallel import only_on_rank
 from khaosz.trainer.metric_util import (
@@ -96,18 +97,20 @@ class CheckpointCallback(TrainCallback):
         self, 
         save_dir: str,  
         interval: int,
-        weight_only: bool = False
+        weight_only: bool = False,
+        state_dict_fn: Optional[Callable[[nn.Module], dict]] = None
     ):
         self.save_dir = save_dir
         self.interval = interval
         self.weight_only = weight_only
-        
+        self.state_dict_fn = state_dict_fn
         self.last_ckpt_iter = 0
     
     def _save_checkpoint(self, context: 'TrainContext'):
         save_path = os.path.join(self.save_dir, f"epoch_{context.epoch}_iter_{context.iteration}")
+        state_dict = self.state_dict_fn(context.model) if self.state_dict_fn else context.optimizer.state_dict()
         context.checkpoint = Checkpoint(
-            optimizer_state_dict=context.optimizer.state_dict(),
+            optimizer_state_dict=state_dict,
             scheduler_state_dict=context.scheduler.state_dict() if context.scheduler else None,
             epoch=context.epoch,
             iteration=context.iteration
diff --git a/khaosz/trainer/train_context.py b/khaosz/trainer/train_context.py
index 91ffa10..4792e2a 100644
--- a/khaosz/trainer/train_context.py
+++ b/khaosz/trainer/train_context.py
@@ -28,6 +28,7 @@ class TrainContext:
     
     world_size: int = field(default=1)
     rank: int = field(default=0)
+    kwargs: dict = field(default_factory=dict)
 
 
 class TrainContextBuilder: