diff --git a/faststack/app.py b/faststack/app.py
index 36aae2b..e3b8333 100644
--- a/faststack/app.py
+++ b/faststack/app.py
@@ -20,10 +20,6 @@
 # Must set before importing PySide6
 os.environ["QT_LOGGING_RULES"] = "qt.qpa.mime.warning=false"
 
-# Type Aliases for readability
-DeletePair = Tuple[Optional[Path], Optional[Path]]  # (src_path, recycle_bin_path)
-DeleteRecord = Tuple[DeletePair, DeletePair]  # (jpg_pair, raw_pair)
-
 import concurrent.futures
 import threading
 import subprocess
@@ -41,7 +37,7 @@
     QMimeData,
     Qt,
     QPoint,
-    QCoreApplication,
+    QCoreApplication,  # noqa: F401 — patched by tests
 )
 from PySide6.QtWidgets import QApplication, QFileDialog
 from PySide6.QtQml import QQmlApplicationEngine
@@ -52,7 +48,10 @@
 from faststack.config import config
 from faststack.logging_setup import setup_logging
 from faststack.models import ImageFile, DecodedImage
-from faststack.io.indexer import find_images, find_images_with_variants
+from faststack.io.indexer import (
+    find_images,
+    find_images_with_variants,
+)  # noqa: F401 — find_images patched by tests
 from faststack.io.variants import (
     VariantGroup,
     build_badge_list,
@@ -6554,10 +6553,15 @@ def execute_crop(self):
                 )
 
             # Coerce elements to int and clamp to [0, 1000]
-            l, t, r, b = [max(0, min(1000, int(x))) for x in crop_box_raw]
+            left, top, right, bottom = [max(0, min(1000, int(x))) for x in crop_box_raw]
 
             # Ensure correct order (left <= right, top <= bottom)
-            crop_box_raw = (min(l, r), min(t, b), max(l, r), max(t, b))
+            crop_box_raw = (
+                min(left, right),
+                min(top, bottom),
+                max(left, right),
+                max(top, bottom),
+            )
 
         except (ValueError, TypeError, AttributeError) as e:
             log.warning("Invalid crop box format: %s", e)
@@ -7536,11 +7540,7 @@ def _collect_active_bins(self) -> set:
             if p.exists() and p.is_dir() and p not in pending_bins
         }
         local_bin = self.image_dir / "image recycle bin"
-        if (
-            local_bin.exists()
-            and local_bin.is_dir()
-            and local_bin not in pending_bins
-        ):
+        if local_bin.exists() and local_bin.is_dir() and local_bin not in pending_bins:
             active.add(local_bin)
         return active
 
@@ -7696,9 +7696,8 @@ def _record_stale(record: DeleteRecord) -> bool:
                 """True if any recycled path in this record was restored."""
                 (_, jpg_bin), (_, raw_bin) = record
                 return (
-                    (jpg_bin is not None and jpg_bin.resolve() in resolved_restored)
-                    or (raw_bin is not None and raw_bin.resolve() in resolved_restored)
-                )
+                    jpg_bin is not None and jpg_bin.resolve() in resolved_restored
+                ) or (raw_bin is not None and raw_bin.resolve() in resolved_restored)
 
             self.delete_history = [
                 r for r in self.delete_history if not _record_stale(r)
diff --git a/faststack/config.py b/faststack/config.py
index 1d9a3d4..c586f74 100644
--- a/faststack/config.py
+++ b/faststack/config.py
@@ -1,11 +1,11 @@
 """Manages application configuration via an INI file."""
 
 import configparser
-import logging
-import sys
 import glob
+import logging
 import os
 import re
+import sys
 from pathlib import PureWindowsPath
 
 from faststack.logging_setup import get_app_data_dir
diff --git a/faststack/deletion_types.py b/faststack/deletion_types.py
index 69dce5c..7d0ddf8 100644
--- a/faststack/deletion_types.py
+++ b/faststack/deletion_types.py
@@ -6,13 +6,11 @@
 
 import threading
 from dataclasses import dataclass, field
+from enum import Enum
 from pathlib import Path
 from typing import Any, List, Optional, Tuple
 
 
-from enum import Enum
-
-
 class DeletionErrorCodes(str, Enum):
     """Standardized error codes for deletion failures."""
 
diff --git a/faststack/imaging/cache.py b/faststack/imaging/cache.py
index 430c489..6ac0353 100644
--- a/faststack/imaging/cache.py
+++ b/faststack/imaging/cache.py
@@ -2,10 +2,11 @@
 
 import inspect
 import logging
+import threading
+import time
 from pathlib import Path
 from typing import Any, Callable, Optional, Union
-import time
-import threading
+
 from cachetools import Cache, LRUCache
 
 log = logging.getLogger(__name__)
diff --git a/faststack/imaging/editor.py b/faststack/imaging/editor.py
index a340ae8..8871648 100644
--- a/faststack/imaging/editor.py
+++ b/faststack/imaging/editor.py
@@ -9,23 +9,23 @@
 import time
 import uuid
 from pathlib import Path
-from typing import Optional, Dict, Any, List, Tuple
+from typing import Any, Dict, List, Optional, Tuple
 
 import numpy as np
-from PIL import Image, ImageFilter, ImageOps, ExifTags
+from PIL import ExifTags, Image, ImageFilter, ImageOps
 
-from faststack.models import DecodedImage
 from faststack.imaging.math_utils import (
-    _srgb_to_linear,
-    _linear_to_srgb,
-    _smoothstep01,
-    _apply_headroom_shoulder,
     _analyze_highlight_state,
-    _lerp,
-    _highlight_recover_linear,
+    _apply_headroom_shoulder,
     _highlight_boost_linear,
+    _highlight_recover_linear,
+    _lerp,
+    _linear_to_srgb,
+    _smoothstep01,
+    _srgb_to_linear,
 )
-from faststack.imaging.orientation import get_exif_orientation, apply_orientation_to_np
+from faststack.imaging.orientation import apply_orientation_to_np, get_exif_orientation
+from faststack.models import DecodedImage
 
 try:
     from PySide6.QtGui import QImage
@@ -34,7 +34,6 @@
 
 from faststack.imaging.optional_deps import cv2
 
-
 log = logging.getLogger(__name__)
 
 # Aspect Ratios for cropping
diff --git a/faststack/imaging/math_utils.py b/faststack/imaging/math_utils.py
index 1cac080..a186a76 100644
--- a/faststack/imaging/math_utils.py
+++ b/faststack/imaging/math_utils.py
@@ -1,6 +1,7 @@
-import numpy as np
 from typing import Optional
 
+import numpy as np
+
 # ----------------------------
 # sRGB ↔ Linear Conversion Helpers
 # ----------------------------
@@ -200,10 +201,6 @@ def _highlight_recover_linear(
     # Use max-channel as brightness metric - handles saturated highlights better than luminance
     brightness = rgb_linear.max(axis=2)
 
-    # Build smooth highlight mask: 0 below pivot, 1 in highlights
-    # Use headroom_ceiling instead of 1.0 for the normalization range
-    mask = _smoothstep01((brightness - pivot) / (headroom_ceiling - pivot + eps))
-
     # Highlights recovery: we want to pull down highlights to reveal detail.
     # Rational compression formula: y = x / (1 + kx).
     # We apply this relative to the pivot.
diff --git a/faststack/imaging/metadata.py b/faststack/imaging/metadata.py
index 35f1cd8..be044cb 100644
--- a/faststack/imaging/metadata.py
+++ b/faststack/imaging/metadata.py
@@ -3,7 +3,8 @@
 from fractions import Fraction
 from pathlib import Path
 from typing import Any, Dict, Optional, Union
-from PIL import Image, ExifTags
+
+from PIL import ExifTags, Image
 
 log = logging.getLogger(__name__)
 
diff --git a/faststack/imaging/orientation.py b/faststack/imaging/orientation.py
index edc7605..692c54c 100644
--- a/faststack/imaging/orientation.py
+++ b/faststack/imaging/orientation.py
@@ -3,6 +3,7 @@
 import logging
 from pathlib import Path
 from typing import Optional
+
 import numpy as np
 from PIL import Image
 
diff --git a/faststack/imaging/prefetch.py b/faststack/imaging/prefetch.py
index 583d1e3..a0bbe2a 100644
--- a/faststack/imaging/prefetch.py
+++ b/faststack/imaging/prefetch.py
@@ -1,19 +1,19 @@
 """Handles prefetching and decoding of adjacent images in a background thread pool."""
 
-import logging
-import os
-import io
 import hashlib
+import io
+import logging
 import mmap
-from pathlib import Path
-from concurrent.futures import Future
-from typing import List, Dict, Optional, Callable
+import os
 import threading
 import time
-
+from concurrent.futures import Future
+from pathlib import Path
+from typing import Callable, Dict, List, Optional
 
 import numpy as np
-from PIL import Image as PILImage, ImageCms
+from PIL import Image as PILImage
+from PIL import ImageCms
 
 try:
     from PySide6.QtCore import QTimer
@@ -22,11 +22,11 @@
     QTimer = None
     QImage = None
 
-from faststack.models import ImageFile, DecodedImage
-from faststack.imaging.jpeg import decode_jpeg_rgb, decode_jpeg_resized
+from faststack.config import config
 from faststack.imaging.cache import build_cache_key
+from faststack.imaging.jpeg import decode_jpeg_resized, decode_jpeg_rgb
 from faststack.imaging.orientation import apply_orientation_to_np
-from faststack.config import config
+from faststack.models import DecodedImage, ImageFile
 from faststack.util.executors import create_daemon_threadpool_executor
 
 log = logging.getLogger(__name__)
@@ -103,6 +103,7 @@ def _make_raw_placeholder(width: int, height: int) -> np.ndarray:
 
     return np.array(img)
 
+
 # ---- Option C: ICC Color Management Setup ----
 SRGB_PROFILE = ImageCms.createProfile("sRGB")
 
diff --git a/faststack/imaging/turbo.py b/faststack/imaging/turbo.py
index a9742f3..006d381 100644
--- a/faststack/imaging/turbo.py
+++ b/faststack/imaging/turbo.py
@@ -10,7 +10,7 @@
 log = logging.getLogger(__name__)
 
 try:
-    from turbojpeg import TurboJPEG, TJPF_RGB
+    from turbojpeg import TJPF_RGB, TurboJPEG
 except ImportError:  # pragma: no cover - exercised via create_turbojpeg
     TurboJPEG = None
     TJPF_RGB = None
diff --git a/faststack/io/deletion.py b/faststack/io/deletion.py
index 64ac168..79a7ef8 100644
--- a/faststack/io/deletion.py
+++ b/faststack/io/deletion.py
@@ -2,8 +2,8 @@
 
 import logging
 from pathlib import Path
-from PySide6.QtWidgets import QMessageBox
 
+from PySide6.QtWidgets import QMessageBox
 
 log = logging.getLogger(__name__)
 
diff --git a/faststack/io/indexer.py b/faststack/io/indexer.py
index 059ee60..2deeedb 100644
--- a/faststack/io/indexer.py
+++ b/faststack/io/indexer.py
@@ -5,15 +5,15 @@
 import re
 import time
 from pathlib import Path
-from typing import List, Dict, Tuple
+from typing import Dict, List, Tuple
 
-from faststack.models import ImageFile
 from faststack.io.variants import (
     VariantGroup,
     build_variant_map,
     norm_path,
     parse_variant_stem,
 )
+from faststack.models import ImageFile
 
 log = logging.getLogger(__name__)
 
diff --git a/faststack/io/sidecar.py b/faststack/io/sidecar.py
index 4daba69..251ceff 100644
--- a/faststack/io/sidecar.py
+++ b/faststack/io/sidecar.py
@@ -8,10 +8,12 @@
 from typing import Literal, Optional, Union, overload
 
 from faststack.io.indexer import JPG_EXTENSIONS, RAW_EXTENSIONS
-from faststack.models import Sidecar, EntryMetadata
+from faststack.models import EntryMetadata, Sidecar
 
 log = logging.getLogger(__name__)
-KNOWN_IMAGE_EXTENSIONS = frozenset(ext.lower() for ext in JPG_EXTENSIONS | RAW_EXTENSIONS)
+KNOWN_IMAGE_EXTENSIONS = frozenset(
+    ext.lower() for ext in JPG_EXTENSIONS | RAW_EXTENSIONS
+)
 
 
 def _entrymetadata_from_json(meta: dict) -> EntryMetadata:
diff --git a/faststack/io/variants.py b/faststack/io/variants.py
index 1be67ee..af02b7a 100644
--- a/faststack/io/variants.py
+++ b/faststack/io/variants.py
@@ -7,6 +7,7 @@
 from dataclasses import dataclass, field
 from pathlib import Path
 from typing import Dict, List, Optional, Tuple
+
 from faststack.io.utils import normalize_path_key as norm_path
 
 # Token-boundary regex: match `-developed` as a real dash-delimited token.
diff --git a/faststack/models.py b/faststack/models.py
index e36d322..c83c5fb 100644
--- a/faststack/models.py
+++ b/faststack/models.py
@@ -2,7 +2,7 @@
 
 import dataclasses
 from pathlib import Path
-from typing import Any, Optional, Dict, List
+from typing import Any, Dict, List, Optional
 
 
 @dataclasses.dataclass
diff --git a/faststack/qml/Main.qml b/faststack/qml/Main.qml
index d7ff313..e84b987 100644
--- a/faststack/qml/Main.qml
+++ b/faststack/qml/Main.qml
@@ -353,7 +353,7 @@ ApplicationWindow {
                 if (uiState && uiState.isGridViewActive) return ""
                 var ratio = zs / fs
                 if (Math.abs(ratio - 1.0) < 0.03) return "Zoom: Fit to window (" + Math.round(zs * 100) + "%)"
-                return "Zoom: " + Math.round(ratio * 100) + "%"
+                return "Zoom: " + Math.round(zs * 100) + "%"
             }
         }
 
diff --git a/faststack/tests/benchmark_decode.py b/faststack/tests/benchmark_decode.py
index 29cbd51..6022463 100644
--- a/faststack/tests/benchmark_decode.py
+++ b/faststack/tests/benchmark_decode.py
@@ -1,8 +1,10 @@
-import time
 import io
+import time
+
 import numpy as np
 from PIL import Image
-from faststack.imaging.jpeg import decode_jpeg_resized, TURBO_AVAILABLE
+
+from faststack.imaging.jpeg import TURBO_AVAILABLE, decode_jpeg_resized
 
 
 def create_test_jpeg(width=6000, height=4000):
diff --git a/faststack/tests/benchmark_decode_bilinear.py b/faststack/tests/benchmark_decode_bilinear.py
index 6b5b069..22a8cf3 100644
--- a/faststack/tests/benchmark_decode_bilinear.py
+++ b/faststack/tests/benchmark_decode_bilinear.py
@@ -1,13 +1,15 @@
-import time
 import io
+import time
+
 import numpy as np
 from PIL import Image
+
 from faststack.imaging.jpeg import (
-    decode_jpeg_rgb,
-    _get_turbojpeg_scaling_factor,
-    TURBO_AVAILABLE,
     JPEG_DECODER,
     TJPF_RGB,
+    TURBO_AVAILABLE,
+    _get_turbojpeg_scaling_factor,
+    decode_jpeg_rgb,
 )
 
 
diff --git a/faststack/tests/check_imports.py b/faststack/tests/check_imports.py
index 7e27361..cb69a43 100644
--- a/faststack/tests/check_imports.py
+++ b/faststack/tests/check_imports.py
@@ -1,34 +1,39 @@
-import sys
+import importlib
 import os
+import sys
 import traceback
 
-# Add current directory to path
-sys.path.append(os.getcwd())
-
-try:
-    print("Importing faststack.app...")
-    import faststack.app
 
-    print("Success faststack.app")
-except ImportError as e:
-    print(f"ImportError faststack.app: {e}")
+def check_import(module_name: str) -> bool:
+    """Try importing a module and print the result."""
+    try:
+        print(f"Importing {module_name}...")
+        importlib.import_module(module_name)
+        print(f"Success {module_name}")
+        return True
+    except ImportError as e:
+        print(f"ImportError {module_name}: {e}")
+        traceback.print_exc()
+        return False
+    except Exception as e:
+        print(f"Non-ImportError during import of {module_name}: {e}")
+        traceback.print_exc()
+        return False
 
-    traceback.print_exc()
-except Exception as e:
-    print(f"Non-ImportError during import of faststack.app: {e}")
 
-    traceback.print_exc()
+def main() -> None:
+    # Add current directory to path
+    sys.path.append(os.getcwd())
 
-try:
-    print("Importing faststack.tests.test_raw_pipeline...")
-    import faststack.tests.test_raw_pipeline
+    failures = []
+    for module in ["faststack.app", "faststack.tests.test_raw_pipeline"]:
+        if not check_import(module):
+            failures.append(module)
 
-    print("Success test_raw_pipeline")
-except ImportError as e:
-    print(f"ImportError test_raw_pipeline: {e}")
+    if failures:
+        print(f"\nFailed imports: {', '.join(failures)}")
+        sys.exit(1)
 
-    traceback.print_exc()
-except Exception as e:
-    print(f"Non-ImportError during import of test_raw_pipeline: {e}")
 
-    traceback.print_exc()
+if __name__ == "__main__":
+    main()
diff --git a/faststack/tests/debug_app_init.py b/faststack/tests/debug_app_init.py
index 6c06fbc..f1a3fc8 100644
--- a/faststack/tests/debug_app_init.py
+++ b/faststack/tests/debug_app_init.py
@@ -1,9 +1,10 @@
-import pytest
-from unittest.mock import MagicMock, patch
+import sys
 from pathlib import Path
-from faststack.app import AppController
+from unittest.mock import MagicMock, patch
+
 from PySide6.QtWidgets import QApplication
-import sys
+
+from faststack.app import AppController
 
 # Ensure QApplication exists before AppController is imported/used
 if not QApplication.instance():
@@ -24,9 +25,10 @@ def test_app_init_only():
     ):
 
         # Create QApplication instance
-        from PySide6.QtWidgets import QApplication
         import sys
 
+        from PySide6.QtWidgets import QApplication
+
         if not QApplication.instance():
             _ = QApplication(sys.argv)
         else:
@@ -34,7 +36,7 @@ def test_app_init_only():
 
         mock_engine = MagicMock()
         try:
-            app = AppController(Path("."), mock_engine)
+            _app = AppController(Path("."), mock_engine)
             print("AppController instantiated successfully")
         except Exception as e:
             print(f"AppController instantiation failed: {e}")
diff --git a/faststack/tests/debug_editor_error.py b/faststack/tests/debug_editor_error.py
index 6ffb2d4..bde987e 100644
--- a/faststack/tests/debug_editor_error.py
+++ b/faststack/tests/debug_editor_error.py
@@ -1,12 +1,11 @@
 import unittest
+from pathlib import Path
 from unittest.mock import MagicMock, patch
+
 import numpy as np
-from pathlib import Path
-import sys
 
 # Ensure faststack is in path
 from faststack.imaging.editor import ImageEditor
-from PIL import Image
 
 
 class TestDebugError(unittest.TestCase):
diff --git a/faststack/tests/debug_metadata.py b/faststack/tests/debug_metadata.py
index 6e94086..5b2df78 100644
--- a/faststack/tests/debug_metadata.py
+++ b/faststack/tests/debug_metadata.py
@@ -1,8 +1,9 @@
+import json
 import sys
 from pathlib import Path
 from unittest.mock import MagicMock, patch
+
 from PIL import ExifTags
-import json
 
 # Add parent directory to path to import faststack
 sys.path.append(str(Path(__file__).parent.parent))
diff --git a/faststack/tests/manual_test_error_handling.py b/faststack/tests/manual_test_error_handling.py
index 4edb2dd..eeca08a 100644
--- a/faststack/tests/manual_test_error_handling.py
+++ b/faststack/tests/manual_test_error_handling.py
@@ -1,8 +1,9 @@
+import logging
 import sys
+from pathlib import Path
 from unittest.mock import MagicMock, patch
+
 import numpy as np
-from pathlib import Path
-import logging
 
 # Configure logging to swallow output
 logging.basicConfig(level=logging.CRITICAL)
diff --git a/faststack/tests/mini_test.py b/faststack/tests/mini_test.py
index 2e30d13..dc2df16 100644
--- a/faststack/tests/mini_test.py
+++ b/faststack/tests/mini_test.py
@@ -1,7 +1,7 @@
-import sys
-from unittest.mock import MagicMock, patch
 import os
+import sys
 import tempfile
+from unittest.mock import MagicMock, patch
 
 print("START_TEST")
 try:
diff --git a/faststack/tests/repro_futures_cleanup.py b/faststack/tests/repro_futures_cleanup.py
index c39960a..20abddc 100644
--- a/faststack/tests/repro_futures_cleanup.py
+++ b/faststack/tests/repro_futures_cleanup.py
@@ -1,10 +1,8 @@
-import unittest
-from unittest.mock import MagicMock
-from concurrent.futures import Future, ThreadPoolExecutor
-import threading
-import time
 import sys
+import unittest
+from concurrent.futures import Future
 from pathlib import Path
+from unittest.mock import MagicMock
 
 # Mock config
 sys.modules["faststack.config"] = MagicMock()
diff --git a/faststack/tests/reproduce_exif_bug.py b/faststack/tests/reproduce_exif_bug.py
index cbfce5f..884ae74 100644
--- a/faststack/tests/reproduce_exif_bug.py
+++ b/faststack/tests/reproduce_exif_bug.py
@@ -1,5 +1,5 @@
-import sys
 import os
+import sys
 from unittest.mock import MagicMock
 
 # Add parent directory to path for standalone execution
@@ -10,6 +10,7 @@
 
 import unittest
 from unittest.mock import patch
+
 from PIL import Image
 
 from faststack.imaging.editor import ImageEditor
diff --git a/faststack/tests/test_auto_levels.py b/faststack/tests/test_auto_levels.py
index 114380c..240d642 100644
--- a/faststack/tests/test_auto_levels.py
+++ b/faststack/tests/test_auto_levels.py
@@ -1,5 +1,6 @@
 import numpy as np
 from PIL import Image
+
 from faststack.imaging.editor import ImageEditor
 
 
diff --git a/faststack/tests/test_cache.py b/faststack/tests/test_cache.py
index 6e0c7cf..490b691 100644
--- a/faststack/tests/test_cache.py
+++ b/faststack/tests/test_cache.py
@@ -100,9 +100,10 @@ class MockBuffer:
 
 def test_get_decoded_image_size_fallback_default():
     """Tests fallback when metadata is missing (should default to 4)."""
-    from faststack.imaging.cache import get_decoded_image_size
     from types import SimpleNamespace
 
+    from faststack.imaging.cache import get_decoded_image_size
+
     class MockBuffer:
         pass
 
diff --git a/faststack/tests/test_cache_invalidation.py b/faststack/tests/test_cache_invalidation.py
index 2b481cf..6c78903 100644
--- a/faststack/tests/test_cache_invalidation.py
+++ b/faststack/tests/test_cache_invalidation.py
@@ -1,8 +1,9 @@
-import sys
 import os
-import time
 import shutil
+import sys
+import time
 from pathlib import Path
+
 import numpy as np
 from PIL import Image
 
@@ -68,7 +69,7 @@ def test_cache_stability():
     # Cleanup
     try:
         shutil.rmtree(test_dir)
-    except:
+    except OSError:
         pass
 
 
diff --git a/faststack/tests/test_cache_replacement_callback.py b/faststack/tests/test_cache_replacement_callback.py
index e70f449..64f915f 100644
--- a/faststack/tests/test_cache_replacement_callback.py
+++ b/faststack/tests/test_cache_replacement_callback.py
@@ -1,6 +1,7 @@
 """Tests for ByteLRUCache eviction callbacks."""
 
 import threading
+
 from faststack.imaging.cache import ByteLRUCache
 
 
diff --git a/faststack/tests/test_config_setters.py b/faststack/tests/test_config_setters.py
index 7c84f1c..e10899e 100644
--- a/faststack/tests/test_config_setters.py
+++ b/faststack/tests/test_config_setters.py
@@ -1,10 +1,8 @@
 import unittest
 from unittest.mock import MagicMock, patch
-import sys
 
 # Important: Do NOT mock sys.modules at the top level.
 # This causes pollution that breaks other tests (like test_cache_invalidation.py).
-
 from faststack.app import AppController
 
 
diff --git a/faststack/tests/test_delete_worker_edge_cases.py b/faststack/tests/test_delete_worker_edge_cases.py
index 58e7c52..ca2f74d 100644
--- a/faststack/tests/test_delete_worker_edge_cases.py
+++ b/faststack/tests/test_delete_worker_edge_cases.py
@@ -1,7 +1,7 @@
 import threading
-from unittest.mock import MagicMock, patch
-import pytest
 from pathlib import Path
+from unittest.mock import patch
+
 from faststack.app import AppController
 from faststack.deletion_types import DeletionErrorCodes
 
diff --git a/faststack/tests/test_deletion_perf_structure.py b/faststack/tests/test_deletion_perf_structure.py
index 2b195d6..a8f8902 100644
--- a/faststack/tests/test_deletion_perf_structure.py
+++ b/faststack/tests/test_deletion_perf_structure.py
@@ -1,14 +1,13 @@
-import pytest
-import os
-from unittest.mock import MagicMock, call, patch
+import sys
 from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+import pytest
+from PySide6.QtWidgets import QApplication
 
 from faststack.app import AppController
 from faststack.models import ImageFile
 
-from PySide6.QtWidgets import QApplication
-import sys
-
 # Ensure QApplication exists before AppController is imported/used in tests
 if not QApplication.instance():
     _qapp = QApplication(sys.argv)
@@ -121,9 +120,7 @@ def test_evict_paths_windows_handling():
 
 def test_model_hashing_no_resolve():
     """Verify PathResolver and ThumbnailModel do NOT call resolve()."""
-    from faststack.thumbnail_view.model import ThumbnailModel
     from faststack.thumbnail_view.provider import PathResolver
-    from faststack.models import ImageFile as ModelImageFile
 
     # Mock Path.resolve to raise exception
     with patch(
diff --git a/faststack/tests/test_deletion_unification.py b/faststack/tests/test_deletion_unification.py
index 7f63ac2..0d8bc85 100644
--- a/faststack/tests/test_deletion_unification.py
+++ b/faststack/tests/test_deletion_unification.py
@@ -1,9 +1,11 @@
-import pytest
-from unittest.mock import Mock, patch
 from pathlib import Path
+from unittest.mock import Mock, patch
+
+import pytest
+
 from faststack.app import AppController
-from faststack.models import ImageFile
 from faststack.deletion_types import DeletionErrorCodes
+from faststack.models import ImageFile
 
 
 @pytest.fixture(scope="session")
diff --git a/faststack/tests/test_developed_sorting.py b/faststack/tests/test_developed_sorting.py
index 8d03a27..ff3d5db 100644
--- a/faststack/tests/test_developed_sorting.py
+++ b/faststack/tests/test_developed_sorting.py
@@ -1,4 +1,5 @@
 import os
+
 from faststack.io.indexer import find_images
 
 
diff --git a/faststack/tests/test_editor.py b/faststack/tests/test_editor.py
index da812e3..aa589a3 100644
--- a/faststack/tests/test_editor.py
+++ b/faststack/tests/test_editor.py
@@ -1,5 +1,6 @@
 import os
 import unittest
+
 from PIL import Image
 
 try:
@@ -25,9 +26,9 @@ def abs_val(x):
 
 class TestEditor(unittest.TestCase):
     def test_save_image_preserves_mtime(self):
+        import shutil
         import tempfile
         from pathlib import Path
-        import shutil
 
         tmp_dir = tempfile.mkdtemp()
         try:
@@ -58,9 +59,9 @@ def test_save_image_preserves_mtime(self):
 
     def test_texture_edit(self):
         editor = ImageEditor()
+        import shutil
         import tempfile
         from pathlib import Path
-        import shutil
 
         try:
             import cv2
diff --git a/faststack/tests/test_editor_error_handling.py b/faststack/tests/test_editor_error_handling.py
index 550c60e..36c5baa 100644
--- a/faststack/tests/test_editor_error_handling.py
+++ b/faststack/tests/test_editor_error_handling.py
@@ -1,8 +1,9 @@
 import sys
 import unittest
+from pathlib import Path
 from unittest.mock import MagicMock, patch
+
 import numpy as np
-from pathlib import Path
 
 # We need to mock cv2 before importing editor if it's not already imported,
 # but since tests run in the same process, we just rely on patching.
diff --git a/faststack/tests/test_editor_integration.py b/faststack/tests/test_editor_integration.py
index ebba82d..058d301 100644
--- a/faststack/tests/test_editor_integration.py
+++ b/faststack/tests/test_editor_integration.py
@@ -1,7 +1,7 @@
+import sys
 import unittest
-from unittest.mock import MagicMock, patch
 from pathlib import Path
-import sys
+from unittest.mock import MagicMock, patch
 
 # Ensure we can import faststack
 sys.path.append(str(Path(__file__).parents[2]))
diff --git a/faststack/tests/test_editor_lifecycle_and_safety.py b/faststack/tests/test_editor_lifecycle_and_safety.py
index 48b745f..23022ad 100644
--- a/faststack/tests/test_editor_lifecycle_and_safety.py
+++ b/faststack/tests/test_editor_lifecycle_and_safety.py
@@ -1,7 +1,7 @@
+import sys
 import unittest
-from unittest.mock import MagicMock, patch
 from pathlib import Path
-import sys
+from unittest.mock import MagicMock, patch
 
 # Ensure we can import faststack
 sys.path.append(str(Path(__file__).parents[2]))
@@ -38,7 +38,7 @@ def setUp(self):
         self.mock_qapp.instance.return_value.aboutToQuit.connect = MagicMock()
 
         # Instantiate AppController
-        with patch("faststack.app.ImageEditor") as mock_editor_cls:
+        with patch("faststack.app.ImageEditor") as _mock_editor_cls:
             self.controller = AppController(Path("."), self.mock_engine)
             self.mock_editor_instance = self.controller.image_editor
 
diff --git a/faststack/tests/test_editor_loading.py b/faststack/tests/test_editor_loading.py
index 56c8755..7a992ce 100644
--- a/faststack/tests/test_editor_loading.py
+++ b/faststack/tests/test_editor_loading.py
@@ -6,12 +6,13 @@
 patch sys.modules['cv2'] before the import happens.
 """
 
+import os
 import sys
+import tempfile
 import unittest
 from unittest.mock import MagicMock, patch
+
 import numpy as np
-import tempfile
-import os
 
 
 class TestImageLoadingFallback(unittest.TestCase):
diff --git a/faststack/tests/test_editor_no_copy.py b/faststack/tests/test_editor_no_copy.py
index 925f7ab..686e62c 100644
--- a/faststack/tests/test_editor_no_copy.py
+++ b/faststack/tests/test_editor_no_copy.py
@@ -1,8 +1,8 @@
 import hashlib
-import numpy as np
-from pathlib import Path
 from unittest.mock import MagicMock, patch
 
+import numpy as np
+
 from faststack.imaging.editor import ImageEditor
 
 
diff --git a/faststack/tests/test_editor_rotation.py b/faststack/tests/test_editor_rotation.py
index 3756778..21b0b5a 100644
--- a/faststack/tests/test_editor_rotation.py
+++ b/faststack/tests/test_editor_rotation.py
@@ -1,11 +1,13 @@
-import pytest
 import math
+
 import numpy as np
+import pytest
 from PIL import Image
+
 from faststack.imaging.editor import (
+    ImageEditor,
     _rotated_rect_with_max_area,
     rotate_autocrop_rgb,
-    ImageEditor,
 )
 
 
diff --git a/faststack/tests/test_executable_validator.py b/faststack/tests/test_executable_validator.py
index ec15f63..3bb40d1 100644
--- a/faststack/tests/test_executable_validator.py
+++ b/faststack/tests/test_executable_validator.py
@@ -1,12 +1,12 @@
 """Tests for executable path validation."""
 
 from pathlib import Path
-from unittest.mock import patch, MagicMock
+from unittest.mock import MagicMock, patch
 
 from faststack.io.executable_validator import (
-    validate_executable_path,
     _is_executable,
     _is_subpath,
+    validate_executable_path,
 )
 
 
diff --git a/faststack/tests/test_executor_shutdown.py b/faststack/tests/test_executor_shutdown.py
index 0f79a23..3c29e2f 100644
--- a/faststack/tests/test_executor_shutdown.py
+++ b/faststack/tests/test_executor_shutdown.py
@@ -1,11 +1,12 @@
-import time
-import threading
 import concurrent.futures
+import threading
+import time
+
 import pytest
+
 from faststack.util.executors import (
-    create_priority_executor,
     create_daemon_threadpool_executor,
-    PriorityExecutor,
+    create_priority_executor,
 )
 
 
diff --git a/faststack/tests/test_exif_compat.py b/faststack/tests/test_exif_compat.py
index ee0c6c2..56de654 100644
--- a/faststack/tests/test_exif_compat.py
+++ b/faststack/tests/test_exif_compat.py
@@ -1,9 +1,10 @@
-import unittest
-from unittest.mock import MagicMock, patch
 import sys
+import unittest
 from pathlib import Path
-from PIL import Image, ExifTags
+from unittest.mock import MagicMock, patch
+
 import numpy as np
+from PIL import ExifTags, Image
 
 # Ensure project root is in sys.path
 project_root = str(Path(__file__).parents[1])
@@ -137,7 +138,7 @@ def test_save_uses_sanitizer_for_sidecar(self):
                 return_value=Path("test-backup.jpg"),
             ),
             patch("PIL.Image.fromarray") as mock_fromarray,
-            patch.object(self.editor, "_write_tiff_16bit") as mock_tiff,
+            patch.object(self.editor, "_write_tiff_16bit") as _mock_tiff,
         ):
             mock_img = MagicMock()
             mock_fromarray.return_value = mock_img
diff --git a/faststack/tests/test_exif_display_rotation.py b/faststack/tests/test_exif_display_rotation.py
index afdda65..ea21092 100644
--- a/faststack/tests/test_exif_display_rotation.py
+++ b/faststack/tests/test_exif_display_rotation.py
@@ -1,13 +1,13 @@
 """Tests for EXIF orientation correction during display."""
 
-import sys
 import shutil
+import sys
 import tempfile
 import unittest
 from pathlib import Path
 
 import numpy as np
-from PIL import Image, ExifTags
+from PIL import ExifTags, Image
 
 # Adjust path to import faststack
 sys.path.insert(0, str(Path(__file__).parents[1]))
diff --git a/faststack/tests/test_exif_orientation.py b/faststack/tests/test_exif_orientation.py
index 45bfbe4..f944237 100644
--- a/faststack/tests/test_exif_orientation.py
+++ b/faststack/tests/test_exif_orientation.py
@@ -2,9 +2,9 @@
 import tempfile
 import unittest
 from pathlib import Path
-from PIL import Image, ExifTags
 from unittest.mock import MagicMock, patch
-import sys
+
+from PIL import ExifTags, Image
 
 from faststack.imaging.editor import ImageEditor
 
@@ -164,7 +164,7 @@ def test_raw_mode_exif_preservation(self):
         # Current logic: We ALWAYS sanitize to 1 because we bake orientation on load.
         # This prevents "double rotation".
 
-        res = self.editor.save_image(write_developed_jpg=True)
+        self.editor.save_image(write_developed_jpg=True)
         developed_path = Path(self.test_dir) / "working_source-developed.jpg"
 
         with Image.open(developed_path) as dev:
diff --git a/faststack/tests/test_fallback_blur.py b/faststack/tests/test_fallback_blur.py
index 2c98e38..90e5b08 100644
--- a/faststack/tests/test_fallback_blur.py
+++ b/faststack/tests/test_fallback_blur.py
@@ -1,7 +1,8 @@
 import unittest
-import numpy as np
 from unittest.mock import patch
 
+import numpy as np
+
 # Import the functionality to test
 from faststack.imaging import editor
 
diff --git a/faststack/tests/test_feedback_fixes.py b/faststack/tests/test_feedback_fixes.py
index d1f6f23..1f27118 100644
--- a/faststack/tests/test_feedback_fixes.py
+++ b/faststack/tests/test_feedback_fixes.py
@@ -1,11 +1,13 @@
-import pytest
-import numpy as np
 from pathlib import Path
+
+import numpy as np
+import pytest
+
 from faststack.imaging.cache import ByteLRUCache
-from faststack.models import DecodedImage
 from faststack.imaging.editor import ImageEditor
-from faststack.io.variants import build_variant_map, norm_path
 from faststack.io.indexer import find_images_with_variants
+from faststack.io.variants import build_variant_map, norm_path
+from faststack.models import DecodedImage
 
 
 def test_cache_evict_callback_payload():
diff --git a/faststack/tests/test_file_locking.py b/faststack/tests/test_file_locking.py
index 137163d..bb9bf73 100644
--- a/faststack/tests/test_file_locking.py
+++ b/faststack/tests/test_file_locking.py
@@ -1,10 +1,10 @@
 """Tests for file locking handling in undo operations."""
 
+import shutil
+import tempfile
 import unittest
-from unittest.mock import MagicMock, patch
 from pathlib import Path
-import tempfile
-import shutil
+from unittest.mock import MagicMock, patch
 
 
 class TestRestoreBackupSafe(unittest.TestCase):
diff --git a/faststack/tests/test_generation_aware_preview.py b/faststack/tests/test_generation_aware_preview.py
index 17be800..6d5ff63 100644
--- a/faststack/tests/test_generation_aware_preview.py
+++ b/faststack/tests/test_generation_aware_preview.py
@@ -1,11 +1,12 @@
-import unittest
-from unittest.mock import MagicMock
-from PySide6.QtGui import QImage
+import os
 
 # Import the class to test (assuming it's importable)
 # We might need to mock imports if they depend on full Qt app structure
 import sys
-import os
+import unittest
+from unittest.mock import MagicMock
+
+from PySide6.QtGui import QImage
 
 # Adjust path to allow imports
 sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), "..")))
@@ -49,7 +50,7 @@ def test_matching_generation(self):
         self.mock_controller._last_rendered_preview_gen = 5
 
         # Request with matching generation
-        img = self.provider.requestImage("0/5", None, None)
+        _img = self.provider.requestImage("0/5", None, None)
 
         # Should be the preview (dark gray placeholder if fails, but here we mocked QImage creation?)
         # Wait, requestImage creates a QImage from the buffer.
diff --git a/faststack/tests/test_handle_failures.py b/faststack/tests/test_handle_failures.py
index 3b6cbe5..b5428bf 100644
--- a/faststack/tests/test_handle_failures.py
+++ b/faststack/tests/test_handle_failures.py
@@ -6,10 +6,10 @@
 from PySide6.QtWidgets import QApplication
 
 from faststack.deletion_types import (
-    DeletionErrorCodes,
     DeleteFailure,
     DeleteJob,
     DeleteResult,
+    DeletionErrorCodes,
 )
 
 # Ensure QApplication exists before importing/using Qt classes
diff --git a/faststack/tests/test_handle_failures_isolated.py b/faststack/tests/test_handle_failures_isolated.py
index 6c634e0..067cc03 100644
--- a/faststack/tests/test_handle_failures_isolated.py
+++ b/faststack/tests/test_handle_failures_isolated.py
@@ -1,11 +1,11 @@
-import sys
-from unittest.mock import MagicMock, patch
 from pathlib import Path
+from unittest.mock import MagicMock, patch
+
 from faststack.deletion_types import (
-    DeletionErrorCodes,
-    DeleteResult,
     DeleteFailure,
     DeleteJob,
+    DeleteResult,
+    DeletionErrorCodes,
 )
 
 # Mocks for global functions that might be called
diff --git a/faststack/tests/test_headroom_semantics.py b/faststack/tests/test_headroom_semantics.py
index e73ab23..9b82541 100644
--- a/faststack/tests/test_headroom_semantics.py
+++ b/faststack/tests/test_headroom_semantics.py
@@ -1,9 +1,10 @@
-import unittest
-import numpy as np
-import sys
 import os
+import sys
+import unittest
 from unittest.mock import MagicMock
 
+import numpy as np
+
 # Mock cv2/turbojpeg
 sys.modules["cv2"] = MagicMock()
 sys.modules["turbojpeg"] = MagicMock()
diff --git a/faststack/tests/test_helicon_cleanup.py b/faststack/tests/test_helicon_cleanup.py
index c8f246c..500a6cb 100644
--- a/faststack/tests/test_helicon_cleanup.py
+++ b/faststack/tests/test_helicon_cleanup.py
@@ -1,8 +1,10 @@
-import pytest
-from unittest.mock import MagicMock, patch
-from pathlib import Path
-import tempfile
 import os
+import tempfile
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+import pytest
+
 from faststack.app import AppController
 from faststack.models import ImageFile
 
diff --git a/faststack/tests/test_highlight_recovery.py b/faststack/tests/test_highlight_recovery.py
index f01a548..bf338d1 100644
--- a/faststack/tests/test_highlight_recovery.py
+++ b/faststack/tests/test_highlight_recovery.py
@@ -6,8 +6,8 @@
 - Handles both 16-bit (headroom) and 8-bit (JPEG) sources
 """
 
-import sys
 import os
+import sys
 
 # Add parent directory to path for standalone execution
 sys.path.insert(
@@ -22,14 +22,15 @@
 
     sys.modules["cv2"] = mock.MagicMock()
 
-import numpy as np
 import time
 
+import numpy as np
+
 from faststack.imaging.math_utils import (
-    _highlight_recover_linear,
-    _highlight_boost_linear,
-    _apply_headroom_shoulder,
     _analyze_highlight_state,
+    _apply_headroom_shoulder,
+    _highlight_boost_linear,
+    _highlight_recover_linear,
 )
 
 
diff --git a/faststack/tests/test_highlight_state_normalization.py b/faststack/tests/test_highlight_state_normalization.py
index 9876e48..dd04a51 100644
--- a/faststack/tests/test_highlight_state_normalization.py
+++ b/faststack/tests/test_highlight_state_normalization.py
@@ -2,6 +2,7 @@
 
 import unittest
 from unittest.mock import MagicMock
+
 from faststack.ui.provider import UIState
 
 
diff --git a/faststack/tests/test_highlights_responsiveness.py b/faststack/tests/test_highlights_responsiveness.py
index 944c80e..2847054 100644
--- a/faststack/tests/test_highlights_responsiveness.py
+++ b/faststack/tests/test_highlights_responsiveness.py
@@ -1,9 +1,10 @@
-import unittest
-import numpy as np
-import sys
 import os
+import sys
+import unittest
 from unittest.mock import MagicMock
 
+import numpy as np
+
 # Mock dependencies
 sys.modules["cv2"] = MagicMock()
 sys.modules["turbojpeg"] = MagicMock()
diff --git a/faststack/tests/test_highlights_v2.py b/faststack/tests/test_highlights_v2.py
index 58f2801..3632856 100644
--- a/faststack/tests/test_highlights_v2.py
+++ b/faststack/tests/test_highlights_v2.py
@@ -1,11 +1,12 @@
-import unittest
-import numpy as np
+import os
 
 # Adjust import path if necessary, but faststack is likely installed or in pythonpath
 import sys
-import os
+import unittest
 from unittest.mock import MagicMock
 
+import numpy as np
+
 # Mock cv2 before importing faststack modules that depend on it
 sys.modules["cv2"] = MagicMock()
 sys.modules["turbojpeg"] = MagicMock()
@@ -42,7 +43,7 @@ def test_analysis_decoupling(self):
         # Create a linear image with some headroom
         linear = np.ones((100, 100, 3), dtype=np.float32) * 1.2
         # sRGB mock indicating some clipping (e.g. 255)
-        srgb = np.ones((100, 100, 3), dtype=np.uint8) * 255
+        _srgb = np.ones((100, 100, 3), dtype=np.uint8) * 255
 
         # Setup editor state to simulate the image being loaded
         # We need this because _apply_edits works on self.float_image/preview logic usually,
@@ -84,8 +85,8 @@ def test_robust_ceiling(self):
             # The hot pixel should be compressed but not NaN
             self.assertLess(out[50, 50, 0], 1000.0)
         except Exception:
-            import traceback
             import sys
+            import traceback
 
             traceback.print_exc(file=sys.__stderr__)
             raise
diff --git a/faststack/tests/test_jump_to_last_uploaded.py b/faststack/tests/test_jump_to_last_uploaded.py
index 80e21da..e445986 100644
--- a/faststack/tests/test_jump_to_last_uploaded.py
+++ b/faststack/tests/test_jump_to_last_uploaded.py
@@ -1,8 +1,10 @@
-import pytest
-from unittest.mock import Mock, patch
 from pathlib import Path
+from unittest.mock import Mock, patch
+
+import pytest
+
 from faststack.app import AppController
-from faststack.models import ImageFile, EntryMetadata
+from faststack.models import EntryMetadata, ImageFile
 
 
 @pytest.fixture(scope="session")
diff --git a/faststack/tests/test_loupe_delete.py b/faststack/tests/test_loupe_delete.py
index 9e5f894..fb60ded 100644
--- a/faststack/tests/test_loupe_delete.py
+++ b/faststack/tests/test_loupe_delete.py
@@ -1,7 +1,8 @@
-import pytest
-from unittest.mock import Mock, patch
-from pathlib import Path
 from dataclasses import dataclass
+from pathlib import Path
+from unittest.mock import Mock, patch
+
+import pytest
 
 from faststack.app import AppController
 
diff --git a/faststack/tests/test_metadata.py b/faststack/tests/test_metadata.py
index 530627e..39dd0b6 100644
--- a/faststack/tests/test_metadata.py
+++ b/faststack/tests/test_metadata.py
@@ -1,9 +1,11 @@
 import unittest
-from unittest.mock import MagicMock, patch
 from pathlib import Path
-from faststack.imaging.metadata import get_exif_data, clean_exif_value, get_exif_brief
+from unittest.mock import MagicMock, patch
+
 from PIL import ExifTags
 
+from faststack.imaging.metadata import clean_exif_value, get_exif_brief, get_exif_data
+
 
 class TestMetadata(unittest.TestCase):
     @patch("pathlib.Path.exists", return_value=True)
diff --git a/faststack/tests/test_new_features.py b/faststack/tests/test_new_features.py
index 2b9fa87..6c96abf 100644
--- a/faststack/tests/test_new_features.py
+++ b/faststack/tests/test_new_features.py
@@ -1,6 +1,8 @@
 import unittest
+
 import numpy as np
 from PIL import Image
+
 from faststack.imaging.editor import ImageEditor
 
 
diff --git a/faststack/tests/test_pairing.py b/faststack/tests/test_pairing.py
index 991544a..33cdf13 100644
--- a/faststack/tests/test_pairing.py
+++ b/faststack/tests/test_pairing.py
@@ -7,7 +7,7 @@
 
 import pytest
 
-from faststack.io.indexer import find_images, _find_raw_pair
+from faststack.io.indexer import _find_raw_pair, find_images
 
 
 @pytest.fixture
diff --git a/faststack/tests/test_permanent_delete.py b/faststack/tests/test_permanent_delete.py
index 85203bb..6097884 100644
--- a/faststack/tests/test_permanent_delete.py
+++ b/faststack/tests/test_permanent_delete.py
@@ -5,8 +5,8 @@
 
 # Import the standalone module, avoiding heavy app imports
 from faststack.io.deletion import (
-    ensure_recycle_bin_dir,
     confirm_permanent_delete,
+    ensure_recycle_bin_dir,
     permanently_delete_image_files,
 )
 
diff --git a/faststack/tests/test_prefetch_concurrency.py b/faststack/tests/test_prefetch_concurrency.py
index 6ee94d1..59f8360 100644
--- a/faststack/tests/test_prefetch_concurrency.py
+++ b/faststack/tests/test_prefetch_concurrency.py
@@ -1,8 +1,9 @@
 import threading
 import time
-import pytest
 from pathlib import Path
 
+import pytest
+
 from faststack.imaging.prefetch import Prefetcher
 
 
diff --git a/faststack/tests/test_prefetch_logic.py b/faststack/tests/test_prefetch_logic.py
index d5004cb..211319c 100644
--- a/faststack/tests/test_prefetch_logic.py
+++ b/faststack/tests/test_prefetch_logic.py
@@ -1,7 +1,7 @@
+import sys
 import unittest
-from unittest.mock import MagicMock
 from concurrent.futures import Future
-import sys
+from unittest.mock import MagicMock
 
 # Mock config before importing prefetcher
 sys.modules["faststack.config"] = MagicMock()
diff --git a/faststack/tests/test_raw_pipeline.py b/faststack/tests/test_raw_pipeline.py
index 02f845b..affafb6 100644
--- a/faststack/tests/test_raw_pipeline.py
+++ b/faststack/tests/test_raw_pipeline.py
@@ -1,13 +1,14 @@
-import unittest
-from unittest.mock import MagicMock, patch
-from pathlib import Path
-import tempfile
+import logging
 import shutil
 import subprocess
+import tempfile
+import unittest
+from dataclasses import dataclass
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
 import numpy as np
 from PIL import Image
-from dataclasses import dataclass
-import logging
 
 from faststack.app import AppController
 from faststack.imaging.editor import ImageEditor
diff --git a/faststack/tests/test_reactive_delete.py b/faststack/tests/test_reactive_delete.py
index c4aad5d..5cb63f1 100644
--- a/faststack/tests/test_reactive_delete.py
+++ b/faststack/tests/test_reactive_delete.py
@@ -1,13 +1,15 @@
-import pytest
-import time
-from unittest.mock import MagicMock, patch, Mock
 from pathlib import Path
+from unittest.mock import MagicMock, Mock, patch
+
+import pytest
+
 from faststack.models import ImageFile
 
 
 @pytest.fixture
 def app_controller(tmp_path):
     from PySide6.QtCore import QCoreApplication
+
     from faststack.app import AppController
 
     app = QCoreApplication.instance()
@@ -101,7 +103,7 @@ def test_async_delete_completion(app_controller):
 
     # 1. Enqueue
     app_controller.delete_current_image()
-    future = app_controller._delete_executor.submit.return_value
+    _future = app_controller._delete_executor.submit.return_value
 
     # 2. Simulate worker side-effects
     recycle_bin = (app_controller.image_dir / "image recycle bin").resolve()
diff --git a/faststack/tests/test_recycle_bin_tracking.py b/faststack/tests/test_recycle_bin_tracking.py
index 521a721..36b6f1d 100644
--- a/faststack/tests/test_recycle_bin_tracking.py
+++ b/faststack/tests/test_recycle_bin_tracking.py
@@ -1,5 +1,7 @@
-import pytest
 from unittest.mock import MagicMock, patch
+
+import pytest
+
 from faststack.app import AppController
 
 
diff --git a/faststack/tests/test_refresh_crash.py b/faststack/tests/test_refresh_crash.py
index 5b4b2fb..4261ba0 100644
--- a/faststack/tests/test_refresh_crash.py
+++ b/faststack/tests/test_refresh_crash.py
@@ -1,6 +1,7 @@
-import pytest
-from pathlib import Path
 from unittest.mock import Mock, patch
+
+import pytest
+
 from faststack.thumbnail_view import ThumbnailModel
 
 
diff --git a/faststack/tests/test_refresh_optimization.py b/faststack/tests/test_refresh_optimization.py
index ebba5dc..5d05619 100644
--- a/faststack/tests/test_refresh_optimization.py
+++ b/faststack/tests/test_refresh_optimization.py
@@ -1,6 +1,7 @@
-import pytest
-from pathlib import Path
 from unittest.mock import Mock, patch
+
+import pytest
+
 from faststack.app import AppController
 
 
diff --git a/faststack/tests/test_rolloff.py b/faststack/tests/test_rolloff.py
index e8ce307..0c2f5ec 100644
--- a/faststack/tests/test_rolloff.py
+++ b/faststack/tests/test_rolloff.py
@@ -1,4 +1,5 @@
 import unittest
+
 import numpy as np
 
 # We check for modules that might be missing and mock them if needed
diff --git a/faststack/tests/test_rotation_unittest.py b/faststack/tests/test_rotation_unittest.py
index dc7da15..c9f09b3 100644
--- a/faststack/tests/test_rotation_unittest.py
+++ b/faststack/tests/test_rotation_unittest.py
@@ -1,5 +1,7 @@
 import unittest
+
 import numpy as np
+
 from faststack.imaging.editor import ImageEditor
 
 
diff --git a/faststack/tests/test_sensitivity.py b/faststack/tests/test_sensitivity.py
index 8096fd1..f8a82c0 100644
--- a/faststack/tests/test_sensitivity.py
+++ b/faststack/tests/test_sensitivity.py
@@ -1,6 +1,7 @@
-import numpy as np
-import sys
 import os
+import sys
+
+import numpy as np
 
 # Add parent directory to sys.path to allow importing faststack
 sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "..")))
diff --git a/faststack/tests/test_sidecar.py b/faststack/tests/test_sidecar.py
index bd0a28e..298fddd 100644
--- a/faststack/tests/test_sidecar.py
+++ b/faststack/tests/test_sidecar.py
@@ -334,7 +334,7 @@ def test_string_with_path_separator_is_path_normalized(mock_sidecar_dir):
     d = mock_sidecar_dir()
     sm = SidecarManager(d, None)
 
-    meta = sm.get_metadata("subdir/photo.CR2")
+    sm.get_metadata("subdir/photo.CR2")
     expected_key = sm.metadata_key_for_path(Path("subdir/photo.CR2"))
 
     assert expected_key in sm.data.entries
diff --git a/faststack/tests/test_startup_opt.py b/faststack/tests/test_startup_opt.py
index 754be19..ebbfe81 100644
--- a/faststack/tests/test_startup_opt.py
+++ b/faststack/tests/test_startup_opt.py
@@ -1,6 +1,7 @@
-import pytest
-from pathlib import Path
 from unittest.mock import Mock, patch
+
+import pytest
+
 from faststack.app import AppController
 
 
diff --git a/faststack/tests/test_startup_optimization.py b/faststack/tests/test_startup_optimization.py
index 732a99a..35bef17 100644
--- a/faststack/tests/test_startup_optimization.py
+++ b/faststack/tests/test_startup_optimization.py
@@ -1,9 +1,8 @@
 import sys
-import os
 from pathlib import Path
 from unittest.mock import MagicMock, patch
-import pytest
 
+import pytest
 from PySide6.QtWidgets import QApplication
 
 # We mock AppController dependencies here
@@ -13,7 +12,7 @@
 @pytest.fixture(scope="session", autouse=True)
 def qapplication():
     if not QApplication.instance():
-        app = QApplication(sys.argv)
+        _app = QApplication(sys.argv)
     yield QApplication.instance()
 
 
diff --git a/faststack/tests/test_thumbnail_ready_emits_datachanged.py b/faststack/tests/test_thumbnail_ready_emits_datachanged.py
index 6413338..e1c8aaa 100644
--- a/faststack/tests/test_thumbnail_ready_emits_datachanged.py
+++ b/faststack/tests/test_thumbnail_ready_emits_datachanged.py
@@ -1,12 +1,12 @@
 """Test that _on_thumbnail_ready correctly emits dataChanged for the matching row."""
 
 from pathlib import Path
-from unittest.mock import MagicMock, patch
+from unittest.mock import MagicMock
 
 import pytest
 
 # Minimal Qt imports needed for the model
-from PySide6.QtCore import Qt, QModelIndex, QCoreApplication
+from PySide6.QtCore import QCoreApplication
 
 
 @pytest.fixture(scope="session")
@@ -21,7 +21,7 @@ def qapp():
 @pytest.fixture
 def thumbnail_model(qapp):
     """Create a ThumbnailModel with fake entries for testing."""
-    from faststack.thumbnail_view.model import ThumbnailModel, ThumbnailEntry
+    from faststack.thumbnail_view.model import ThumbnailEntry, ThumbnailModel
 
     model = ThumbnailModel(
         base_directory=Path("/fake/dir"),
diff --git a/faststack/tests/test_turbo.py b/faststack/tests/test_turbo.py
index 6e90094..2192565 100644
--- a/faststack/tests/test_turbo.py
+++ b/faststack/tests/test_turbo.py
@@ -69,9 +69,7 @@ def fake_decoder(path=None):
     assert decoder is None
     assert available is False
 
-    warning_records = [
-        r for r in caplog.records if r.levelno == logging.WARNING
-    ]
+    warning_records = [r for r in caplog.records if r.levelno == logging.WARNING]
     assert len(warning_records) == 1
     assert "Falling back to Pillow" in warning_records[0].message
     assert "3 location(s) tried" in warning_records[0].message
@@ -94,9 +92,7 @@ def fake_decoder(path=None):
     with caplog.at_level(logging.DEBUG):
         turbo.create_turbojpeg()
 
-    debug_records = [
-        r for r in caplog.records if r.levelno == logging.DEBUG
-    ]
+    debug_records = [r for r in caplog.records if r.levelno == logging.DEBUG]
     debug_text = " ".join(r.message for r in debug_records)
     assert "default loader" in debug_text
     assert "C:/one/turbojpeg.dll" in debug_text
@@ -114,9 +110,7 @@ def test_missing_turbojpeg_package_emits_one_warning(monkeypatch, caplog):
     assert decoder is None
     assert available is False
 
-    warning_records = [
-        r for r in caplog.records if r.levelno == logging.WARNING
-    ]
+    warning_records = [r for r in caplog.records if r.levelno == logging.WARNING]
     assert len(warning_records) == 1
     assert "PyTurboJPEG not found" in warning_records[0].message
     assert "Pillow" in warning_records[0].message
diff --git a/faststack/tests/test_ui_prefetch_safety.py b/faststack/tests/test_ui_prefetch_safety.py
index f8f0492..9a0616a 100644
--- a/faststack/tests/test_ui_prefetch_safety.py
+++ b/faststack/tests/test_ui_prefetch_safety.py
@@ -1,6 +1,7 @@
 import unittest
-from unittest.mock import MagicMock, patch
 from pathlib import Path
+from unittest.mock import MagicMock
+
 from faststack.ui.provider import UIState
 
 
diff --git a/faststack/tests/test_ui_state_recycle.py b/faststack/tests/test_ui_state_recycle.py
index e759b42..144bf2d 100644
--- a/faststack/tests/test_ui_state_recycle.py
+++ b/faststack/tests/test_ui_state_recycle.py
@@ -1,6 +1,5 @@
-import pytest
 from unittest.mock import Mock
-from pathlib import Path
+
 from faststack.ui.provider import UIState
 
 
diff --git a/faststack/tests/test_undo_refactor.py b/faststack/tests/test_undo_refactor.py
index a80e1cc..f624545 100644
--- a/faststack/tests/test_undo_refactor.py
+++ b/faststack/tests/test_undo_refactor.py
@@ -1,12 +1,14 @@
-import pytest
-from unittest.mock import MagicMock, patch
 import shutil
+from unittest.mock import MagicMock, patch
+
+import pytest
 
 
 # Create a dummy fixture for AppController that uses the real class but mocks dependencies
 @pytest.fixture
 def app_controller(tmp_path):
     from PySide6.QtCore import QCoreApplication
+
     from faststack.app import AppController
 
     # Ensure QCoreApplication exists
diff --git a/faststack/tests/test_variants.py b/faststack/tests/test_variants.py
index 9e46ad0..f492996 100644
--- a/faststack/tests/test_variants.py
+++ b/faststack/tests/test_variants.py
@@ -1,20 +1,14 @@
 """Tests for variant (backup + developed) parsing, grouping, and integration."""
 
-import os
-import pytest
 from pathlib import Path
-from unittest.mock import MagicMock
 
 from faststack.io.variants import (
-    parse_variant_stem,
-    build_variant_map,
     build_badge_list,
+    build_variant_map,
     norm_path,
-    VariantInfo,
-    VariantGroup,
+    parse_variant_stem,
 )
 
-
 # ── parse_variant_stem ──────────────────────────────────────────────────────
 
 
diff --git a/faststack/tests/test_variants_logic.py b/faststack/tests/test_variants_logic.py
index 193282f..5870a8d 100644
--- a/faststack/tests/test_variants_logic.py
+++ b/faststack/tests/test_variants_logic.py
@@ -1,7 +1,8 @@
-import unittest
 import os
+import unittest
 from pathlib import Path
-from faststack.io.variants import build_variant_map, VariantGroup, norm_path
+
+from faststack.io.variants import build_variant_map, norm_path
 
 
 class TestVariantsLogic(unittest.TestCase):
diff --git a/faststack/tests/test_version_sort.py b/faststack/tests/test_version_sort.py
index e57b72a..e4abf0a 100644
--- a/faststack/tests/test_version_sort.py
+++ b/faststack/tests/test_version_sort.py
@@ -1,5 +1,5 @@
-import unittest
 import re
+import unittest
 from pathlib import PureWindowsPath
 
 
diff --git a/faststack/tests/thumbnail_view/test_folder_stats.py b/faststack/tests/thumbnail_view/test_folder_stats.py
index fb36a10..2220377 100644
--- a/faststack/tests/thumbnail_view/test_folder_stats.py
+++ b/faststack/tests/thumbnail_view/test_folder_stats.py
@@ -1,17 +1,19 @@
 """Tests for folder_stats module."""
 
 import json
+
 import pytest
+
 from faststack.thumbnail_view.folder_stats import (
     FolderStats,
-    read_folder_stats,
-    clear_stats_cache,
-    clear_raw_count_cache,
-    _stats_cache,
-    _scan_folder_files,
     _compute_coverage_buckets,
+    _scan_folder_files,
+    _stats_cache,
+    clear_raw_count_cache,
+    clear_stats_cache,
     count_images_in_folder,
     get_file_counts_by_extension,
+    read_folder_stats,
 )
 
 
diff --git a/faststack/tests/thumbnail_view/test_model.py b/faststack/tests/thumbnail_view/test_model.py
index 7cdd83a..d9d0e50 100644
--- a/faststack/tests/thumbnail_view/test_model.py
+++ b/faststack/tests/thumbnail_view/test_model.py
@@ -1,9 +1,8 @@
 # faststack/thumbnail_view/model.py
 from __future__ import annotations
 
-import os
 import sys
-from dataclasses import dataclass, field
+from dataclasses import dataclass
 from pathlib import Path
 from typing import Any, Callable, Iterable, Mapping, Optional
 
@@ -242,7 +241,6 @@ def refresh(self) -> None:
         Rebuild the entries list based on filesystem + filters.
         """
         cur = self.current_directory.resolve()
-        base = self.base_directory.resolve()
 
         folders: list[ThumbnailEntry] = []
         files: list[ThumbnailEntry] = []
diff --git a/faststack/tests/thumbnail_view/test_prefetcher_priority.py b/faststack/tests/thumbnail_view/test_prefetcher_priority.py
index 46b7629..21c563d 100644
--- a/faststack/tests/thumbnail_view/test_prefetcher_priority.py
+++ b/faststack/tests/thumbnail_view/test_prefetcher_priority.py
@@ -1,7 +1,9 @@
 import time
-from unittest.mock import MagicMock, patch
-import pytest
 from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
 from faststack.thumbnail_view.prefetcher import ThumbnailCache, ThumbnailPrefetcher
 
 
diff --git a/faststack/tests/thumbnail_view/test_provider_logic.py b/faststack/tests/thumbnail_view/test_provider_logic.py
index 09dfe69..1f16584 100644
--- a/faststack/tests/thumbnail_view/test_provider_logic.py
+++ b/faststack/tests/thumbnail_view/test_provider_logic.py
@@ -1,16 +1,17 @@
 """Tests for _parse_id logic and cache-hit decode recovery in ThumbnailProvider."""
 
-import pytest
 from pathlib import Path
 from unittest.mock import MagicMock
 
+import pytest
+from PySide6.QtCore import QSize
+
+from faststack.thumbnail_view.prefetcher import ThumbnailCache
 from faststack.thumbnail_view.provider import (
-    ThumbnailProvider,
-    PLACEHOLDER_COLOR,
     ERROR_COLOR,
+    PLACEHOLDER_COLOR,
+    ThumbnailProvider,
 )
-from faststack.thumbnail_view.prefetcher import ThumbnailCache
-from PySide6.QtCore import QSize
 
 
 class TestProviderLogic:
diff --git a/faststack/tests/thumbnail_view/test_reason_tracking.py b/faststack/tests/thumbnail_view/test_reason_tracking.py
index 6aae26c..d545828 100644
--- a/faststack/tests/thumbnail_view/test_reason_tracking.py
+++ b/faststack/tests/thumbnail_view/test_reason_tracking.py
@@ -1,9 +1,10 @@
 """Tests for thumbnail source reason tracking in ThumbnailModel."""
 
 from pathlib import Path
+
 import pytest
-from PySide6.QtCore import Qt, QModelIndex
-from faststack.thumbnail_view.model import ThumbnailModel, ThumbnailEntry
+
+from faststack.thumbnail_view.model import ThumbnailEntry, ThumbnailModel
 
 
 @pytest.fixture
@@ -95,6 +96,7 @@ def test_clear_next_source_reason_method(model):
 def test_refresh_sets_deferred_clear(model):
     """refresh() should NOT synchronously clear reason."""
     from unittest.mock import patch
+
     from faststack.models import ImageFile
 
     with patch("faststack.thumbnail_view.model.find_images") as mock_find:
diff --git a/faststack/tests/thumbnail_view/test_selection.py b/faststack/tests/thumbnail_view/test_selection.py
index 6406721..153dc1b 100644
--- a/faststack/tests/thumbnail_view/test_selection.py
+++ b/faststack/tests/thumbnail_view/test_selection.py
@@ -2,7 +2,7 @@
 
 import pytest
 
-from faststack.thumbnail_view.model import ThumbnailModel, ThumbnailEntry
+from faststack.thumbnail_view.model import ThumbnailEntry, ThumbnailModel
 
 
 @pytest.fixture
diff --git a/faststack/tests/thumbnail_view/test_thumbnail_ready.py b/faststack/tests/thumbnail_view/test_thumbnail_ready.py
index f93347b..64bc55b 100644
--- a/faststack/tests/thumbnail_view/test_thumbnail_ready.py
+++ b/faststack/tests/thumbnail_view/test_thumbnail_ready.py
@@ -1,11 +1,9 @@
 """Test that _on_thumbnail_ready only fires for matching size IDs."""
 
 import sys
-from pathlib import Path
 from unittest.mock import MagicMock
 
 import pytest
-
 from PySide6.QtCore import QCoreApplication
 
 from faststack.io.utils import compute_path_hash
diff --git a/faststack/thumbnail_view/__init__.py b/faststack/thumbnail_view/__init__.py
index b6c85ec..6cd99ff 100644
--- a/faststack/thumbnail_view/__init__.py
+++ b/faststack/thumbnail_view/__init__.py
@@ -1,9 +1,9 @@
 """Thumbnail grid view components for FastStack."""
 
 from .folder_stats import FolderStats, read_folder_stats
-from .model import ThumbnailModel, ThumbnailEntry
-from .prefetcher import ThumbnailPrefetcher, ThumbnailCache
-from .provider import ThumbnailProvider, PathResolver
+from .model import ThumbnailEntry, ThumbnailModel
+from .prefetcher import ThumbnailCache, ThumbnailPrefetcher
+from .provider import PathResolver, ThumbnailProvider
 
 __all__ = [
     "FolderStats",
diff --git a/faststack/thumbnail_view/model.py b/faststack/thumbnail_view/model.py
index 50c175a..342fbd8 100644
--- a/faststack/thumbnail_view/model.py
+++ b/faststack/thumbnail_view/model.py
@@ -1,27 +1,25 @@
 """ThumbnailModel for QML GridView with file/folder entries."""
 
-import hashlib
 import logging
 import os
 import time
 from bisect import bisect_left
 from dataclasses import dataclass
 from pathlib import Path
-from typing import Dict, List, Optional, Set, Callable
+from typing import Callable, Dict, List, Optional, Set
 
 from PySide6.QtCore import (
     QAbstractListModel,
     QModelIndex,
+    Qt,
     QThread,
     QTimer,
-    Qt,
     Signal,
     Slot,
 )
 
-from faststack.models import ImageFile
-from faststack.io.utils import compute_path_hash, normalize_path_key
 from faststack.io.indexer import find_images
+from faststack.io.utils import compute_path_hash, normalize_path_key
 from faststack.thumbnail_view.folder_stats import (
     FolderStats,
     count_images_in_folder,
@@ -411,7 +409,9 @@ def refresh(self):
                         meta = self._get_metadata(img.path)
                         if not isinstance(meta, dict):
                             # Ensure it's a dict before .get()
-                            log.debug("Metadata for %s is not a dict: %r", img.path, meta)
+                            log.debug(
+                                "Metadata for %s is not a dict: %r", img.path, meta
+                            )
                             continue
 
                         if all(meta.get(flag, False) for flag in flags):
@@ -630,9 +630,7 @@ def _add_images_to_entries(
                         is_favorite = meta.get("favorite", False)
                         is_todo = meta.get("todo", False)
                     else:
-                        log.debug(
-                            "Metadata for %s is not a dict: %r", img.path, meta
-                        )
+                        log.debug("Metadata for %s is not a dict: %r", img.path, meta)
                 except Exception as e:
                     log.debug("Error getting metadata for %s: %s", img.path, e)
 
diff --git a/faststack/thumbnail_view/prefetcher.py b/faststack/thumbnail_view/prefetcher.py
index afae214..bd69377 100644
--- a/faststack/thumbnail_view/prefetcher.py
+++ b/faststack/thumbnail_view/prefetcher.py
@@ -2,33 +2,34 @@
 
 import logging
 import os
+import threading
 import time
 from collections import OrderedDict
 from concurrent.futures import Future
 from pathlib import Path
 from threading import Lock
-import threading
-from typing import Dict, Optional, Set, Tuple, Callable, TYPE_CHECKING
+from typing import TYPE_CHECKING, Callable, Dict, Optional, Tuple
 
 if TYPE_CHECKING:
     from faststack.imaging.cache import ByteLRUCache
 
-import numpy as np
 import io
-from PIL import Image
 from contextlib import nullcontext
 
+import numpy as np
+from PIL import Image
+
+import faststack.util.thumb_debug as thumb_debug
+from faststack.imaging.orientation import apply_orientation_to_np, get_exif_orientation
 from faststack.imaging.turbo import TJPF_RGB, create_turbojpeg
-from faststack.util.executors import create_priority_executor
-from faststack.imaging.orientation import get_exif_orientation, apply_orientation_to_np
 from faststack.io.utils import compute_path_hash
-import faststack.util.thumb_debug as thumb_debug
+from faststack.util.executors import create_priority_executor
 
 log = logging.getLogger(__name__)
 
 # Optional Qt dispatch so callbacks always run on Qt thread when available
 try:
-    from PySide6.QtCore import QObject, Signal, Qt, QCoreApplication
+    from PySide6.QtCore import QCoreApplication, QObject, Qt, Signal
 
     class _ReadyEmitter(QObject):
         ready = Signal(str)
diff --git a/faststack/thumbnail_view/provider.py b/faststack/thumbnail_view/provider.py
index d27ccf5..d684955 100644
--- a/faststack/thumbnail_view/provider.py
+++ b/faststack/thumbnail_view/provider.py
@@ -2,21 +2,20 @@
 
 import logging
 import time
-from urllib.parse import unquote
 from pathlib import Path
-from typing import TYPE_CHECKING, Optional, NamedTuple
-
-import faststack.util.thumb_debug as thumb_debug
+from typing import TYPE_CHECKING, NamedTuple, Optional
+from urllib.parse import unquote
 
 from PySide6.QtCore import QSize
-from PySide6.QtGui import QImage, QColor
+from PySide6.QtGui import QColor, QImage
 from PySide6.QtQuick import QQuickImageProvider
 
+import faststack.util.thumb_debug as thumb_debug
 from faststack.io.utils import compute_path_hash
 
 if TYPE_CHECKING:
     from faststack.thumbnail_view.model import ThumbnailModel
-    from faststack.thumbnail_view.prefetcher import ThumbnailPrefetcher, ThumbnailCache
+    from faststack.thumbnail_view.prefetcher import ThumbnailCache, ThumbnailPrefetcher
 
 log = logging.getLogger(__name__)
 
@@ -100,7 +99,7 @@ def _create_placeholder(self, size: int, color: QColor) -> QImage:
 
     def _create_folder_placeholder(self, size: int) -> QImage:
         """Create a folder icon placeholder."""
-        from PySide6.QtGui import QPainter, QPen, QBrush
+        from PySide6.QtGui import QBrush, QPainter, QPen
 
         image = QImage(size, size, QImage.Format.Format_RGB888)
         image.fill(FOLDER_COLOR)
diff --git a/faststack/ui/keystrokes.py b/faststack/ui/keystrokes.py
index 7807528..21ed5af 100644
--- a/faststack/ui/keystrokes.py
+++ b/faststack/ui/keystrokes.py
@@ -1,5 +1,6 @@
 # faststack/ui/keystrokes.py
 import logging
+
 from PySide6.QtCore import Qt
 
 log = logging.getLogger(__name__)
diff --git a/faststack/ui/provider.py b/faststack/ui/provider.py
index d0c93bb..9f74476 100644
--- a/faststack/ui/provider.py
+++ b/faststack/ui/provider.py
@@ -1,15 +1,16 @@
 """QML Image Provider and application state bridge."""
 
-import logging
 import collections
+import logging
 import threading
-from PySide6.QtCore import QObject, Signal, Property, Slot, Qt
+from pathlib import Path
+
+from PySide6.QtCore import Property, QObject, Qt, Signal, Slot
 from PySide6.QtGui import QImage
 from PySide6.QtQuick import QQuickImageProvider
 
 from faststack.config import config
 from faststack.imaging.optional_deps import HAS_OPENCV
-from pathlib import Path
 
 # Try to import QColorSpace if available (Qt 6+)
 try:
diff --git a/faststack/util/executors.py b/faststack/util/executors.py
index 880ce81..72bb2cc 100644
--- a/faststack/util/executors.py
+++ b/faststack/util/executors.py
@@ -12,7 +12,7 @@
 
 
 import weakref
-from concurrent.futures.thread import _worker, _threads_queues
+from concurrent.futures.thread import _threads_queues, _worker
 
 
 class DaemonThreadPoolExecutor(ThreadPoolExecutor):
diff --git a/faststack/util/thumb_debug.py b/faststack/util/thumb_debug.py
index 7a8dfc7..5616356 100644
--- a/faststack/util/thumb_debug.py
+++ b/faststack/util/thumb_debug.py
@@ -1,12 +1,12 @@
 """Thumbnail pipeline debug logging and performance tracing."""
 
+import itertools
 import logging
-import time
 import threading
-import itertools
+import time
 from contextlib import contextmanager
-from typing import Dict, Optional, Any
 from pathlib import Path
+from typing import Any, Dict, Optional
 
 log = logging.getLogger(__name__)
 
diff --git a/pyproject.toml b/pyproject.toml
index 5983085..e6562ed 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -6,7 +6,7 @@ build-backend = "setuptools.build_meta"
 name = "faststack"
 version = "1.6.1"
 authors = [
-    { name="Alan Rockefeller"},
+    { name = "Alan Rockefeller" },
 ]
 description = "Ultra-fast JPG Viewer for Focus Stacking Selection"
 readme = "README.md"
@@ -25,13 +25,15 @@ dependencies = [
     "cachetools>=5.0,<6.0",
     "watchdog>=4.0,<5.0",
     "Pillow>=10.0,<11.0",
-    # CRITICAL FIX: OpenCV 4.10+ is required for NumPy 2.0 binary compatibility
+    # OpenCV 4.10+ might be required for NumPy 2.0 binary compatibility
     "opencv-python>=4.10.0,<5.0",
 ]
 
 [project.optional-dependencies]
 dev = [
     "pytest>=8.0,<9.0",
+    "ruff>=0.13,<0.14",
+    "black>=25.0,<26.0",
     "build",
     "twine",
 ]
@@ -54,8 +56,34 @@ minversion = "8.0"
 testpaths = ["faststack/tests"]
 python_files = ["test_*.py"]
 
-# FIX: Add import-mode=importlib to fix resolution errors
+# Use importlib mode to avoid test import-path resolution issues
 addopts = "--import-mode=importlib -p no:cacheprovider -p no:doctest --basetemp=./var/pytest-temp"
 
 norecursedirs = ["var", ".venv", "cache", "faststack.egg-info", "__pycache__"]
 pythonpath = ["."]
+
+
+[tool.black]
+line-length = 88
+target-version = ["py312"]
+
+[tool.ruff]
+line-length = 88
+target-version = "py312"
+
+[tool.ruff.lint]
+select = ["E", "F", "W", "I"]
+ignore = ["E501"]
+
+[tool.ruff.lint.per-file-ignores]
+"faststack/app.py" = ["E402", "I001", "F401"]
+"faststack/tests/run_loading_tests.py" = ["E402"]
+"faststack/tests/repro_futures_cleanup.py" = ["E402"]
+"faststack/tests/reproduce_exif_bug.py" = ["E402"]
+"faststack/tests/test_exif_compat.py" = ["E402"]
+"faststack/tests/test_headroom_semantics.py" = ["E402"]
+"faststack/tests/test_highlights_responsiveness.py" = ["E402"]
+"faststack/tests/test_highlights_v2.py" = ["E402"]
+"faststack/tests/test_prefetch_logic.py" = ["E402"]
+"faststack/util/executors.py" = ["E402"]
+"faststack/tests/test_highlight_recovery.py" = ["F401"]