diff --git a/dmlcloud/core/callbacks.py b/dmlcloud/core/callbacks.py
index 7c981aa..1623f06 100644
--- a/dmlcloud/core/callbacks.py
+++ b/dmlcloud/core/callbacks.py
@@ -10,6 +10,7 @@
 from omegaconf import OmegaConf
 from progress_table import ProgressTable
 
+from ..git import git_diff
 from ..util.logging import DevNullIO, experiment_header, general_diagnostics, IORedirector
 from ..util.wandb import wandb_is_initialized, wandb_set_startup_timeout
 from . import logging as dml_logging
@@ -89,6 +90,7 @@ class CbPriority(IntEnum):
     CHECKPOINT = -190
     STAGE_TIMER = -180
     DIAGNOSTICS = -170
+    GIT = -160
     METRIC_REDUCTION = -160
 
     OBJECT_METHODS = 0
@@ -436,3 +438,23 @@ def post_run(self, pipe):
         dml_logging.info(f'Finished training in {pipe.stop_time - pipe.start_time} ({pipe.stop_time})')
         if pipe.checkpointing_enabled:
             dml_logging.info(f'Outputs have been saved to {pipe.checkpoint_dir}')
+
+
+class GitDiffCallback(Callback):
+    """
+    A callback that prints a git diff and if checkpointing is enabled, saves it to the checkpoint directory.
+    """
+
+    def pre_run(self, pipe):
+        diff = git_diff()
+
+        if pipe.checkpointing_enabled:
+            self._save(pipe.checkpoint_dir.path / 'git_diff.txt', diff)
+
+        msg = '* GIT-DIFF:\n'
+        msg += '\n'.join('\t' + line for line in diff.splitlines())
+        dml_logging.info(msg)
+
+    def _save(self, path, diff):
+        with open(path, 'w') as f:
+            f.write(diff)
diff --git a/dmlcloud/core/pipeline.py b/dmlcloud/core/pipeline.py
index d97b87f..a36024f 100644
--- a/dmlcloud/core/pipeline.py
+++ b/dmlcloud/core/pipeline.py
@@ -15,6 +15,7 @@
     CheckpointCallback,
     CsvCallback,
     DiagnosticsCallback,
+    GitDiffCallback,
     WandbCallback,
 )
 from .checkpoint import CheckpointDir, find_slurm_checkpoint, generate_checkpoint_path
@@ -113,6 +114,7 @@ def __init__(self, config: Optional[Union[OmegaConf, Dict]] = None, name: Option
         self.callbacks = CallbackList()
 
         self.add_callback(DiagnosticsCallback(), CbPriority.DIAGNOSTICS)
+        self.add_callback(GitDiffCallback(), CbPriority.GIT)
         self.add_callback(_ForwardCallback(), CbPriority.OBJECT_METHODS)  # methods have priority 0
 
         if dist.is_gloo_available():
diff --git a/dmlcloud/git.py b/dmlcloud/git.py
index 05800c7..dcb11d9 100644
--- a/dmlcloud/git.py
+++ b/dmlcloud/git.py
@@ -90,5 +90,9 @@ def git_hash(short=False):
 
 
 def git_diff():
+    """
+    Returns the output of `git diff -U0 --no-color HEAD`
+    """
+
     process = run_in_project(['git', 'diff', '-U0', '--no-color', 'HEAD'])
     return process.stdout.decode('utf-8').strip()