diff --git a/repo_cloner/lib/detector.py b/repo_cloner/lib/detector.py
index cf810dd..55f0ce0 100644
--- a/repo_cloner/lib/detector.py
+++ b/repo_cloner/lib/detector.py
@@ -3,6 +3,7 @@ from pathlib import Path
 import logging
 import json
 from typing import Callable
+from datetime import datetime
 
 log = logging.getLogger("rc.detector")
 
@@ -38,7 +39,8 @@ class DetectedCommit:
 
 	@property
 	def date(self) -> int:
-		return self._date
+		dt = datetime.fromtimestamp(self._date)
+		return dt.strftime("%d-%m-%Y, %H:%M:%S")
 
 	@property
 	def is_tag(self) -> bool:
@@ -69,6 +71,7 @@ class Detector:
 	_repo: RepoTool = None
 	_repo_path: Path = None
 	_detector_dir: Path = None
+	_detector_sum: Path = None
 	_executed: DiskStoredList = None
 	_branches: DiskStoredRefs = None
 	_tags: DiskStoredRefs = None
@@ -79,6 +82,7 @@ class Detector:
 		self._repo_path = Path(repo_path)
 		self._repo = RepoTool(repo_path)
 		self._detector_dir = Path(cache_dir).joinpath("detector")
+		self._detector_sum = Path(cache_dir).joinpath("detectorSum")
 		if not self._detector_dir.exists():
 			log.debug(f"Creating detector dir")
 			self._detector_dir.mkdir()
@@ -146,6 +150,22 @@ class Detector:
 		for tag, commit in self._repo.list_tags().items():
 			self._tags.update(tag, commit)
 
+	"""
+	returns true if  detector run needs to be done
+	"""
+
+	def check_fingerprint(self) -> bool:
+		log.info(f"Checking repo-detector fingerprint")
+		if not self._detector_sum.exists():
+			log.debug(f"Fingerprint file does not exist - run needed")
+			return True
+		old_fingerprint = self._detector_sum.read_text().strip()
+		return not old_fingerprint == self._repo.repo_fingerprint
+
+	def persist_fingerprint(self):
+		log.debug(f"Persisting detector fingerprint")
+		self._detector_sum.write_text(str(self._repo.repo_fingerprint))
+
 	def run(self, callback: Callable[[DetectedCommit], None]) -> int:
 		log.info(f"Running commit detector")
 		new_branches = self._repo.list_branches()
@@ -207,4 +227,5 @@ class Detector:
 			env = DetectedCommit(env)
 			executed_count += 1
 			callback(env)
+		self.persist_fingerprint()
 		return executed_count
diff --git a/tests/lib/test_detector.py b/tests/lib/test_detector.py
index ca05d20..df2e6df 100644
--- a/tests/lib/test_detector.py
+++ b/tests/lib/test_detector.py
@@ -2,7 +2,7 @@ import logging
 
 from repo_cloner.lib import Detector, DetectedCommit
 import pytest
-from unittest.mock import patch, MagicMock
+from unittest.mock import patch, MagicMock, PropertyMock
 from git import Actor
 from cloner_test_fixtures import cloner_dir_struct
 from collections import namedtuple
@@ -211,6 +211,45 @@ def test_initialize_caches(tmp_path):
 	assert dict(json.loads(cache_dir.joinpath("tags").read_text())) == tags
 
 
+def test_check_fingerprint(tmp_path):
+	mocks = {
+		'repo_fingerprint': PropertyMock(return_value = "FingerPrint"),
+	}
+
+	repo = tmp_path.joinpath("repo.git")
+	cache_dir = tmp_path.joinpath("cache")
+	cache_dir.mkdir()
+	fp_file = cache_dir.joinpath("detectorSum")
+
+	with patch.multiple("repo_cloner.lib.RepoTool", **mocks):
+		det = Detector(repo, cache_dir, "Mocked")
+		# file does not exist
+		assert det.check_fingerprint()
+
+		fp_file.touch()
+		assert det.check_fingerprint()
+
+		fp_file.write_text("FingerPrint")
+
+		assert not det.check_fingerprint()
+
+
+def test_persist_fingerprint(tmp_path):
+	mocks = {
+		'repo_fingerprint': PropertyMock(return_value = "FingerPrint"),
+	}
+
+	repo = tmp_path.joinpath("repo.git")
+	cache_dir = tmp_path.joinpath("cache")
+	cache_dir.mkdir()
+	fp_file = cache_dir.joinpath("detectorSum")
+
+	with patch.multiple("repo_cloner.lib.RepoTool", **mocks):
+		det = Detector(repo, cache_dir, "Mocked")
+		det.persist_fingerprint()
+		assert fp_file.read_text().strip() == "FingerPrint"
+
+
 def test_run(tmp_path, caplog):
 	stamp = 1659533160
 	executed = []
@@ -298,9 +337,10 @@ def test_run(tmp_path, caplog):
 						 for commit in commits_new]
 
 	mocks = {
-		'list_commits':  MagicMock(return_value = commits_named_new),
-		'list_branches': MagicMock(return_value = branches_new),
-		'list_tags':     MagicMock(return_value = tags_new),
+		'list_commits':     MagicMock(return_value = commits_named_new),
+		'list_branches':    MagicMock(return_value = branches_new),
+		'list_tags':        MagicMock(return_value = tags_new),
+		'repo_fingerprint': PropertyMock(return_value = "some-fingerprint"),
 	}
 
 	repo = tmp_path.joinpath("repo.git")