diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 61fbd30..ef1ae06 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -19,7 +19,7 @@ repos:
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
   # Ruff version.
-  rev: v0.15.6
+  rev: v0.16.4
   hooks:
     - id: ruff
       args: [--fix, --exit-non-zero-on-fix]
diff --git a/setup.py b/setup.py
index cbb86cc..48730d6 100644
--- a/setup.py
+++ b/setup.py
@@ -12,7 +12,7 @@
 if __name__ == "__main__":
     try:
         setup(use_scm_version={"version_scheme": "no-guess-dev"})
-    except:  # noqa
+    except:
         print(
             "\n\nAn error occurred while building the project, "
             "please ensure you have the most updated version of setuptools, "
diff --git a/src/spatialexperiment/__init__.py b/src/spatialexperiment/__init__.py
index 8fd41e7..8dd20a4 100644
--- a/src/spatialexperiment/__init__.py
+++ b/src/spatialexperiment/__init__.py
@@ -26,11 +26,11 @@
 )
 
 __all__ = [
-    "read_tenx_visium",
-    "SpatialExperiment",
     "LoadedSpatialImage",
     "RemoteSpatialImage",
+    "SpatialExperiment",
     "StoredSpatialImage",
     "VirtualSpatialImage",
     "construct_spatial_image_class",
+    "read_tenx_visium",
 ]
diff --git a/src/spatialexperiment/_combineutils.py b/src/spatialexperiment/_combineutils.py
index 0ff2805..51763a3 100644
--- a/src/spatialexperiment/_combineutils.py
+++ b/src/spatialexperiment/_combineutils.py
@@ -1,15 +1,14 @@
 from __future__ import annotations
-from typing import List, Tuple
 
-from warnings import warn
-from copy import deepcopy
 import itertools
+from copy import deepcopy
+from warnings import warn
 
-from biocframe import BiocFrame
 import biocutils as ut
+from biocframe import BiocFrame
 
 
-def _append_indices_to_samples(bframes: List[BiocFrame]) -> List[BiocFrame]:
+def _append_indices_to_samples(bframes: list[BiocFrame]) -> list[BiocFrame]:
     """Append indices to sample IDs for a list of `BiocFrames`.
 
     For each `BiocFrame`, appends an index to all sample IDs to ensure uniqueness
@@ -29,7 +28,7 @@ def _append_indices_to_samples(bframes: List[BiocFrame]) -> List[BiocFrame]:
     return modified_bframes
 
 
-def merge_spatial_frames(x: List["SpatialExperiment"], relaxed: bool = False) -> Tuple[BiocFrame, BiocFrame]:
+def merge_spatial_frames(x: list[SpatialExperiment], relaxed: bool = False) -> tuple[BiocFrame, BiocFrame]:
     """Merge column data and image data from multiple ``SpatialExperiment`` objects.
 
     If duplicate sample IDs exist across objects, appends indices to make them unique.
@@ -70,7 +69,7 @@ def merge_spatial_frames(x: List["SpatialExperiment"], relaxed: bool = False) ->
     return _new_cols, _new_img_data
 
 
-def merge_spatial_coordinates(spatial_coords: List[BiocFrame], relaxed: bool = False) -> BiocFrame:
+def merge_spatial_coordinates(spatial_coords: list[BiocFrame], relaxed: bool = False) -> BiocFrame:
     """Merge spatial coordinates from multiple frames.
 
     Args:
diff --git a/src/spatialexperiment/_imgutils.py b/src/spatialexperiment/_imgutils.py
index 6d47b0c..279c7bd 100644
--- a/src/spatialexperiment/_imgutils.py
+++ b/src/spatialexperiment/_imgutils.py
@@ -1,12 +1,12 @@
-from typing import Union, List
-
 import os
 from io import BytesIO
 from pathlib import Path
 from urllib.parse import urlparse
+
 import numpy as np
-from PIL import Image
 from biocframe import BiocFrame
+from PIL import Image
+
 from .spatialimage import construct_spatial_image_class
 
 __author__ = "keviny2"
@@ -43,7 +43,7 @@ def read_image(input_image):
 
 
 def construct_img_data(
-    img: Union[str, os.PathLike], scale_factor: str, sample_id: str, image_id: str, load: bool = True
+    img: str | os.PathLike, scale_factor: str, sample_id: str, image_id: str, load: bool = True
 ) -> BiocFrame:
     """
     Construct an image data dataframe.
@@ -77,9 +77,9 @@ def construct_img_data(
 
 def get_img_idx(
     img_data: BiocFrame,
-    sample_id: Union[str, bool, None] = None,
-    image_id: Union[str, bool, None] = None,
-) -> List[int]:
+    sample_id: str | bool | None = None,
+    image_id: str | bool | None = None,
+) -> list[int]:
     """
     Retrieve the row index/indices of image(s) with matching 'sample_id' and 'image_id' from the 'img_data'.
 
diff --git a/src/spatialexperiment/_initutils.py b/src/spatialexperiment/_initutils.py
index 2f794af..35c97d8 100644
--- a/src/spatialexperiment/_initutils.py
+++ b/src/spatialexperiment/_initutils.py
@@ -1,19 +1,19 @@
 from copy import deepcopy
-from typing import List, Tuple
 
 from biocframe import BiocFrame
 from PIL import Image
-from .spatialimage import construct_spatial_image_class
 from summarizedexperiment._frameutils import _sanitize_frame
 
+from .spatialimage import construct_spatial_image_class
+
 __author__ = "keviny2"
 __copyright__ = "keviny2"
 __license__ = "MIT"
 
 
 def construct_spatial_coords_from_names(
-    spatial_coords_names: List[str], column_data: BiocFrame
-) -> Tuple[BiocFrame, BiocFrame]:
+    spatial_coords_names: list[str], column_data: BiocFrame
+) -> tuple[BiocFrame, BiocFrame]:
     """Construct the `spatial_coords` dataframe from names.
 
     Args:
@@ -54,8 +54,8 @@ def construct_spatial_coords_from_names(
 def construct_img_data(
     sample_id: str,
     image_id: str,
-    image_sources: List[str],
-    scale_factors: List[float],
+    image_sources: list[str],
+    scale_factors: list[float],
     load_image: bool = False,
 ) -> BiocFrame:
     """Construct the image data for a `SpatialExperiment`.
diff --git a/src/spatialexperiment/_validators.py b/src/spatialexperiment/_validators.py
index b2b884d..25533b8 100644
--- a/src/spatialexperiment/_validators.py
+++ b/src/spatialexperiment/_validators.py
@@ -1,7 +1,7 @@
 import warnings
 
-from biocframe import BiocFrame
 import biocutils as ut
+from biocframe import BiocFrame
 
 __author__ = "keviny2"
 __copyright__ = "keviny2"
diff --git a/src/spatialexperiment/io/tenx_visium.py b/src/spatialexperiment/io/tenx_visium.py
index 43c3855..f19ca98 100644
--- a/src/spatialexperiment/io/tenx_visium.py
+++ b/src/spatialexperiment/io/tenx_visium.py
@@ -1,17 +1,17 @@
 """Creates a ``SpatialExperiment`` from the Space Ranger output directories for 10x Genomics Visium spatial gene expression data"""
 
-from typing import List, Union, Optional
-from warnings import warn
+import json
 import os
 import re
-import json
+from warnings import warn
 
-from biocframe import BiocFrame
 import biocutils as ut
+from biocframe import BiocFrame
 from singlecellexperiment import read_tenx_mtx
-from ..spatialexperiment import SpatialExperiment
+
 from .._imgutils import construct_img_data
 from .._initutils import construct_spatial_coords_from_names
+from ..spatialexperiment import SpatialExperiment
 
 
 def read_tissue_positions(tissue_positions_path) -> "pd.DataFrame":
@@ -46,8 +46,8 @@ def read_tissue_positions(tissue_positions_path) -> "pd.DataFrame":
 
 def read_img_data(
     path: str = ".",
-    sample_ids: Optional[List[str]] = None,
-    image_sources: Optional[List[str]] = None,
+    sample_ids: list[str] | None = None,
+    image_sources: list[str] | None = None,
     scale_factors: str = None,
     load: bool = True,
 ) -> BiocFrame:
@@ -118,11 +118,11 @@ def read_img_data(
 
 
 def read_tenx_visium(
-    samples: List[Union[str, os.PathLike]],
-    sample_ids: Optional[List[str]] = None,
+    samples: list[str | os.PathLike],
+    sample_ids: list[str] | None = None,
     type: str = "HDF5",
     data: str = "filtered",
-    images: List[str] = "lowres",
+    images: list[str] = "lowres",
     load: bool = True,
 ):
     """Create a ``SpatialExperiment`` from the Space Ranger output directories for 10x Genomics Visium spatial gene expression data.
diff --git a/src/spatialexperiment/spatialexperiment.py b/src/spatialexperiment/spatialexperiment.py
index 5c805fa..b52fe5d 100644
--- a/src/spatialexperiment/spatialexperiment.py
+++ b/src/spatialexperiment/spatialexperiment.py
@@ -1,7 +1,8 @@
 from __future__ import annotations
 
+from collections.abc import Sequence
 from pathlib import Path
-from typing import Any, Dict, List, Optional, Sequence, Tuple, Union
+from typing import Any
 from urllib.parse import urlparse
 from warnings import warn
 
@@ -56,21 +57,21 @@ class SpatialExperiment(SingleCellExperiment):
 
     def __init__(
         self,
-        assays: Dict[str, Any] = None,
-        row_ranges: Optional[GRangesOrGRangesList] = None,
-        row_data: Optional[BiocFrame] = None,
-        column_data: Optional[BiocFrame] = None,
-        row_names: Optional[List[str]] = None,
-        column_names: Optional[List[str]] = None,
-        metadata: Optional[Union[Dict[str, Any], ut.NamedList]] = None,
-        reduced_dims: Optional[Dict[str, Any]] = None,
-        main_experiment_name: Optional[str] = None,
-        alternative_experiments: Optional[Dict[str, Any]] = None,
+        assays: dict[str, Any] = None,
+        row_ranges: GRangesOrGRangesList | None = None,
+        row_data: BiocFrame | None = None,
+        column_data: BiocFrame | None = None,
+        row_names: list[str] | None = None,
+        column_names: list[str] | None = None,
+        metadata: dict[str, Any] | ut.NamedList | None = None,
+        reduced_dims: dict[str, Any] | None = None,
+        main_experiment_name: str | None = None,
+        alternative_experiments: dict[str, Any] | None = None,
         alternative_experiment_check_dim_names: bool = True,
-        row_pairs: Optional[Any] = None,
-        column_pairs: Optional[Any] = None,
-        spatial_coords: Optional[Union[BiocFrame, np.ndarray]] = None,
-        img_data: Optional[BiocFrame] = None,
+        row_pairs: Any | None = None,
+        column_pairs: Any | None = None,
+        spatial_coords: BiocFrame | np.ndarray | None = None,
+        img_data: BiocFrame | None = None,
         _validate: bool = True,
         **kwargs,
     ) -> None:
@@ -376,7 +377,7 @@ def __str__(self) -> str:
         output += f"row_pairs({len(self.row_pair_names)}): {ut.print_truncated_list(self.row_pair_names)}\n"
         output += f"column_pairs({len(self.column_pair_names)}): {ut.print_truncated_list(self.column_pair_names)}\n"
 
-        output += f"metadata({str(len(self.metadata))}): {ut.print_truncated_list(list(self.metadata.keys()), sep=' ', include_brackets=False, transform=lambda y: y)}\n"
+        output += f"metadata({len(self.metadata)!s}): {ut.print_truncated_list(list(self.metadata.keys()), sep=' ', include_brackets=False, transform=lambda y: y)}\n"
 
         output += f"spatial_coords columns({len(self.spatial_coords_names)}): {ut.print_truncated_list(self.spatial_coords_names)}\n"
         output += f"img_data columns({len(self._img_data.column_names)}): {ut.print_truncated_list(self._img_data.column_names)}"
@@ -387,7 +388,7 @@ def __str__(self) -> str:
     #####>> spatial_coords <<#####
     ##############################
 
-    def get_spatial_coordinates(self) -> Union[BiocFrame, np.ndarray]:
+    def get_spatial_coordinates(self) -> BiocFrame | np.ndarray:
         """Access spatial coordinates.
 
         Returns:
@@ -401,7 +402,7 @@ def get_spatial_coords(self) -> BiocFrame:
 
     def set_spatial_coordinates(
         self,
-        spatial_coords: Optional[Union[BiocFrame, np.ndarray]],
+        spatial_coords: BiocFrame | np.ndarray | None,
         in_place: bool = False,
     ) -> SpatialExperiment:
         """Set new spatial coordinates.
@@ -436,7 +437,7 @@ def set_spatial_coordinates(
 
     def set_spatial_coords(
         self,
-        spatial_coords: Optional[Union[BiocFrame, np.ndarray]],
+        spatial_coords: BiocFrame | np.ndarray | None,
         in_place: bool = False,
     ) -> SpatialExperiment:
         """Alias for :py:meth:`~set_spatial_coordinates`."""
@@ -448,7 +449,7 @@ def spatial_coords(self) -> BiocFrame:
         return self.get_spatial_coordinates()
 
     @spatial_coords.setter
-    def spatial_coords(self, spatial_coords: Optional[Union[BiocFrame, np.ndarray]]):
+    def spatial_coords(self, spatial_coords: BiocFrame | np.ndarray | None):
         """Alias for :py:meth:`~set_spatial_coordinates`."""
         warn(
             "Setting property 'spatial_coords' is an in-place operation, use 'set_spatial_coordinates' instead.",
@@ -462,7 +463,7 @@ def spatial_coordinates(self) -> BiocFrame:
         return self.get_spatial_coordinates()
 
     @spatial_coordinates.setter
-    def spatial_coordinates(self, spatial_coords: Optional[Union[BiocFrame, np.ndarray]]):
+    def spatial_coordinates(self, spatial_coords: BiocFrame | np.ndarray | None):
         """Alias for :py:meth:`~set_spatial_coordinates`."""
         warn(
             "Setting property 'spatial_coords' is an in-place operation, use 'set_spatial_coordinates' instead.",
@@ -474,7 +475,7 @@ def spatial_coordinates(self, spatial_coords: Optional[Union[BiocFrame, np.ndarr
     ##>> spatial_coords_names <<##
     ##############################
 
-    def get_spatial_coordinates_names(self) -> List[str]:
+    def get_spatial_coordinates_names(self) -> list[str]:
         """Access spatial coordinates names.
 
         Returns:
@@ -485,12 +486,12 @@ def get_spatial_coordinates_names(self) -> List[str]:
 
         return self._spatial_coords.columns.as_list()
 
-    def get_spatial_coords_names(self) -> List[str]:
+    def get_spatial_coords_names(self) -> list[str]:
         """Alias for :py:meth:`~get_spatial_coordinate_names`."""
         return self.get_spatial_coordinate_names()
 
     def set_spatial_coordinates_names(
-        self, spatial_coords_names: List[str], in_place: bool = False
+        self, spatial_coords_names: list[str], in_place: bool = False
     ) -> SpatialExperiment:
         """Set new spatial coordinates names.
 
@@ -518,17 +519,17 @@ def set_spatial_coordinates_names(
         output._spatial_coords = new_spatial_coords
         return output
 
-    def set_spatial_coords_names(self, spatial_coords_names: List[str], in_place: bool = False) -> SpatialExperiment:
+    def set_spatial_coords_names(self, spatial_coords_names: list[str], in_place: bool = False) -> SpatialExperiment:
         """Alias for :py:meth:`~set_spatial_coordinates_names`."""
         return self.set_spatial_coordinates_names(spatial_coords_names=spatial_coords_names, in_place=in_place)
 
     @property
-    def spatial_coords_names(self) -> List[str]:
+    def spatial_coords_names(self) -> list[str]:
         """Alias for :py:meth:`~get_spatial_coordinates_names`."""
         return self.get_spatial_coordinates_names()
 
     @spatial_coords_names.setter
-    def spatial_coords_names(self, spatial_coords_names: List[str]):
+    def spatial_coords_names(self, spatial_coords_names: list[str]):
         """Alias for :py:meth:`~set_spatial_coordinates_names`."""
         warn(
             "Setting property 'spatial_coords_names' is an in-place operation, use 'set_spatial_coordinates_names' instead.",
@@ -537,12 +538,12 @@ def spatial_coords_names(self, spatial_coords_names: List[str]):
         self.set_spatial_coordinates_names(spatial_coords_names=spatial_coords_names, in_place=True)
 
     @property
-    def spatial_coordinates_names(self) -> List[str]:
+    def spatial_coordinates_names(self) -> list[str]:
         """Alias for :py:meth:`~get_spatial_coordinates_names`."""
         return self.get_spatial_coordinates_names()
 
     @spatial_coordinates_names.setter
-    def spatial_coordinates_names(self, spatial_coords_names: List[str]):
+    def spatial_coordinates_names(self, spatial_coords_names: list[str]):
         """Alias for :py:meth:`~set_spatial_coordinates_names`."""
         warn(
             "Setting property 'spatial_coords_names' is an in-place operation, use 'set_spatial_coordinates_names' instead.",
@@ -566,7 +567,7 @@ def get_img_data(self) -> BiocFrame:
         """Alias for :py:meth:`~get_image_data`."""
         return self.get_image_data()
 
-    def set_image_data(self, img_data: Optional[BiocFrame], in_place: bool = False) -> SpatialExperiment:
+    def set_image_data(self, img_data: BiocFrame | None, in_place: bool = False) -> SpatialExperiment:
         """Set new image data.
 
         Args:
@@ -633,9 +634,9 @@ def image_data(self, img_data: BiocFrame):
 
     def get_scale_factors(
         self,
-        sample_id: Union[str, bool, None] = None,
-        image_id: Union[str, bool, None] = None,
-    ) -> List[float]:
+        sample_id: str | bool | None = None,
+        image_id: str | bool | None = None,
+    ) -> list[float]:
         """Return scale factor(s) of image(s) based on the provided sample and image ids.
             See :py:meth:`~get_img` for more details on the behavior for various
             combinations of `sample_id` and `image_id` values.
@@ -667,7 +668,7 @@ def get_scale_factors(
 
     def set_column_data(
         self,
-        cols: Optional[BiocFrame],
+        cols: BiocFrame | None,
         replace_column_names: bool = False,
         in_place: bool = False,
     ) -> SpatialExperiment:
@@ -712,8 +713,8 @@ def set_column_data(
 
     def get_slice(
         self,
-        rows: Optional[Union[str, int, bool, Sequence]],
-        columns: Optional[Union[str, int, bool, Sequence]],
+        rows: str | int | bool | Sequence | None,
+        columns: str | int | bool | Sequence | None,
     ) -> SpatialExperiment:
         """Alias for :py:attr:`~__getitem__`."""
 
@@ -756,9 +757,9 @@ def get_slice(
 
     def get_img(
         self,
-        sample_id: Union[str, bool, None] = None,
-        image_id: Union[str, bool, None] = None,
-    ) -> Union[VirtualSpatialImage, List[VirtualSpatialImage]]:
+        sample_id: str | bool | None = None,
+        image_id: str | bool | None = None,
+    ) -> VirtualSpatialImage | list[VirtualSpatialImage]:
         """Retrieve spatial images based on the provided sample and image ids.
 
         Args:
@@ -818,10 +819,10 @@ def get_img(
 
     def add_img(
         self,
-        image_source: Union[Image.Image, np.ndarray, str, Path],
+        image_source: Image.Image | np.ndarray | str | Path,
         scale_factor: float,
-        sample_id: Union[str, bool, None],
-        image_id: Union[str, bool, None],
+        sample_id: str | bool | None,
+        image_id: str | bool | None,
         load: bool = True,
         in_place: bool = False,
     ) -> SpatialExperiment:
@@ -886,7 +887,7 @@ def add_img(
         return output
 
     def remove_img(
-        self, sample_id: Union[str, bool, None] = None, image_id: Union[str, bool, None] = None, in_place: bool = False
+        self, sample_id: str | bool | None = None, image_id: str | bool | None = None, in_place: bool = False
     ) -> SpatialExperiment:
         """Remove an image entry.
 
@@ -930,10 +931,10 @@ def remove_img(
 
     def img_source(
         self,
-        sample_id: Union[str, bool, None] = None,
-        image_id: Union[str, bool, None] = None,
+        sample_id: str | bool | None = None,
+        image_id: str | bool | None = None,
         path=False,
-    ) -> Union[str, Path, None, List[Union[str, Path]]]:
+    ) -> str | Path | None | list[str | Path]:
         """Retrieve the source(s) for images stored in the SpatialExperiment object.
 
         Args:
@@ -972,7 +973,7 @@ def img_source(
 
         return img_sources
 
-    def img_raster(self, sample_id=None, image_id=None) -> Union[Image.Image, List[Image.Image], None]:
+    def img_raster(self, sample_id=None, image_id=None) -> Image.Image | list[Image.Image] | None:
         """Retrieve and load (if necessary) the images stored in the SpatialExperiment object.
 
         Args:
@@ -1025,7 +1026,7 @@ def to_spatial_experiment():
 
     def to_anndata(
         self, include_alternative_experiments: bool = False
-    ) -> Tuple["anndata.AnnData", Dict[str, "anndata.AnnData"]]:
+    ) -> tuple[anndata.AnnData, dict[str, anndata.AnnData]]:
         """Transform :py:class:`~SpatialExperiment`-like into a :py:class:`~anndata.AnnData` representation.
 
         This method converts the main experiment data, spatial coordinates,
@@ -1128,7 +1129,7 @@ def combine_columns(*x: SpatialExperiment) -> SpatialExperiment:
         _new_rdim = merge_generic(x, by="row", attr="reduced_dims")
     except Exception as e:
         warn(
-            f"Cannot combine 'reduced_dimensions' across experiments, {str(e)}",
+            f"Cannot combine 'reduced_dimensions' across experiments, {e!s}",
             UserWarning,
         )
 
@@ -1137,7 +1138,7 @@ def combine_columns(*x: SpatialExperiment) -> SpatialExperiment:
         _new_alt_expt = merge_generic(x, by="column", attr="alternative_experiments")
     except Exception as e:
         warn(
-            f"Cannot combine 'alternative_experiments' across experiments, {str(e)}",
+            f"Cannot combine 'alternative_experiments' across experiments, {e!s}",
             UserWarning,
         )
 
@@ -1197,7 +1198,7 @@ def relaxed_combine_columns(
         _new_rdim = relaxed_merge_numpy_generic(x, by="row", attr="reduced_dims")
     except Exception as e:
         warn(
-            f"Cannot combine 'reduced_dimensions' across experiments, {str(e)}",
+            f"Cannot combine 'reduced_dimensions' across experiments, {e!s}",
             UserWarning,
         )
 
@@ -1206,7 +1207,7 @@ def relaxed_combine_columns(
         _new_alt_expt = relaxed_merge_generic(x, by="column", attr="alternative_experiments")
     except Exception as e:
         warn(
-            f"Cannot combine 'alternative_experiments' across experiments, {str(e)}",
+            f"Cannot combine 'alternative_experiments' across experiments, {e!s}",
             UserWarning,
         )
 
diff --git a/src/spatialexperiment/spatialimage.py b/src/spatialexperiment/spatialimage.py
index a4a3f0b..758fd3c 100644
--- a/src/spatialexperiment/spatialimage.py
+++ b/src/spatialexperiment/spatialimage.py
@@ -3,7 +3,6 @@
 from abc import abstractmethod
 from functools import lru_cache
 from pathlib import Path
-from typing import Optional, Tuple, Union
 from urllib.parse import urlparse
 from warnings import warn
 
@@ -22,7 +21,7 @@
 class VirtualSpatialImage(ut.BiocObject):
     """Base class for spatial images."""
 
-    def __init__(self, metadata: Optional[dict] = None):
+    def __init__(self, metadata: dict | None = None):
         super().__init__(metadata=metadata)
 
     #########################
@@ -53,13 +52,13 @@ def affine(self, scale_factor: float = 1.0) -> Affine:
         """
         return Affine.scale(scale_factor, scale_factor)
 
-    def get_dimensions(self) -> Tuple[int, int]:
+    def get_dimensions(self) -> tuple[int, int]:
         """Get image dimensions (width, height) in pixels."""
         img = self.img_raster()
         return img.size
 
     @property
-    def dimensions(self) -> Tuple[int, int]:
+    def dimensions(self) -> tuple[int, int]:
         """Alias for :py:meth:`~get_dimensions`."""
         return self.get_dimensions()
 
@@ -68,7 +67,7 @@ def dimensions(self) -> Tuple[int, int]:
     ############################
 
     @abstractmethod
-    def img_source(self, as_path: bool = False) -> Union[str, Path, None]:
+    def img_source(self, as_path: bool = False) -> str | Path | None:
         """Get the source of the image.
 
         Args:
@@ -77,12 +76,10 @@ def img_source(self, as_path: bool = False) -> Union[str, Path, None]:
         Returns:
             Source path/URL of the image, or None if loaded in memory.
         """
-        pass
 
     @abstractmethod
     def img_raster(self) -> Image.Image:
         """Get the image as a PIL Image object."""
-        pass
 
     def to_numpy(self, **kwargs) -> np.ndarray:
         """Convert the image raster to a NumPy array.
@@ -132,7 +129,7 @@ def mirror_img(self, axis: str = "h") -> "LoadedSpatialImage":
         )
 
 
-def _sanitize_loaded_image(image: Union[Image.Image, np.ndarray]) -> Image.Image:
+def _sanitize_loaded_image(image: Image.Image | np.ndarray) -> Image.Image:
     if isinstance(image, np.ndarray):
         # trying to infer mode for multi-channel arrays if not RGBA/RGB
         if image.ndim == 3:
@@ -159,7 +156,7 @@ def _sanitize_loaded_image(image: Union[Image.Image, np.ndarray]) -> Image.Image
 class LoadedSpatialImage(VirtualSpatialImage):
     """Class for images loaded into memory."""
 
-    def __init__(self, image: Union[Image.Image, np.ndarray], metadata: Optional[dict] = None):
+    def __init__(self, image: Image.Image | np.ndarray, metadata: dict | None = None):
         """Initialize the object.
 
         Args:
@@ -260,7 +257,7 @@ def __str__(self) -> str:
         """
         output = f"class: {type(self).__name__}\n"
         output += f"image: ({self._image})\n"
-        output += f"metadata({str(len(self.metadata))}): {ut.print_truncated_list(list(self.metadata.keys()), sep=' ', include_brackets=False, transform=lambda y: y)}\n"
+        output += f"metadata({len(self.metadata)!s}): {ut.print_truncated_list(list(self.metadata.keys()), sep=' ', include_brackets=False, transform=lambda y: y)}\n"
 
         return output
 
@@ -272,7 +269,7 @@ def get_image(self) -> Image.Image:
         """Get the PIL Image object."""
         return self._image
 
-    def set_image(self, image: Union[Image.Image, np.ndarray], in_place: bool = False) -> "LoadedSpatialImage":
+    def set_image(self, image: Image.Image | np.ndarray, in_place: bool = False) -> "LoadedSpatialImage":
         """Set new image.
 
         Args:
@@ -295,7 +292,7 @@ def image(self) -> Image.Image:
         return self.get_image()
 
     @image.setter
-    def image(self, image: Union[Image.Image, np.ndarray]):
+    def image(self, image: Image.Image | np.ndarray):
         """Alias for :py:attr:`~set_image` with ``in_place = True``.
 
         As this mutates the original object, a warning is raised.
@@ -308,7 +305,7 @@ def image(self, image: Union[Image.Image, np.ndarray]):
 
     def img_source(self, as_path: bool = False) -> None:
         """Get the source of the loaded image (always None for in-memory)."""
-        return None
+        return
 
     ############################
     ######>> img utils <<#######
@@ -319,7 +316,7 @@ def img_raster(self) -> Image.Image:
         return self._image
 
 
-def _sanitize_path(path: Union[str, Path]) -> Path:
+def _sanitize_path(path: str | Path) -> Path:
     _path = Path(path).resolve()
     if not _path.exists():
         raise FileNotFoundError(f"Image file not found: {path}")
@@ -330,7 +327,7 @@ def _sanitize_path(path: Union[str, Path]) -> Path:
 class StoredSpatialImage(VirtualSpatialImage):
     """Class for images stored on local filesystem."""
 
-    def __init__(self, path: Union[str, Path], metadata: Optional[dict] = None):
+    def __init__(self, path: str | Path, metadata: dict | None = None):
         """Initialize the object.
 
         Args:
@@ -414,8 +411,8 @@ def __str__(self) -> str:
             A pretty-printed string containing the contents of this object.
         """
         output = f"class: {type(self).__name__}\n"
-        output += f"path: ({str(self._path)})\n"
-        output += f"metadata({str(len(self.metadata))}): {ut.print_truncated_list(list(self.metadata.keys()), sep=' ', include_brackets=False, transform=lambda y: y)}\n"
+        output += f"path: ({self._path!s})\n"
+        output += f"metadata({len(self.metadata)!s}): {ut.print_truncated_list(list(self.metadata.keys()), sep=' ', include_brackets=False, transform=lambda y: y)}\n"
 
         return output
 
@@ -427,7 +424,7 @@ def get_path(self) -> Path:
         """Get the path to the image file."""
         return self._path
 
-    def set_path(self, path: Union[str, Path], in_place: bool = False) -> "StoredSpatialImage":
+    def set_path(self, path: str | Path, in_place: bool = False) -> "StoredSpatialImage":
         """Update the path to the image file.
 
         Args:
@@ -455,7 +452,7 @@ def path(self) -> Path:
         return self.get_path()
 
     @path.setter
-    def path(self, path: Union[str, Path]):
+    def path(self, path: str | Path):
         """Alias for :py:attr:`~set_path` with ``in_place = True``.
 
         As this mutates the original object, a warning is raised.
@@ -499,7 +496,7 @@ def _validate_url(url: str):
 class RemoteSpatialImage(VirtualSpatialImage):
     """Class for remotely hosted images."""
 
-    def __init__(self, url: str, metadata: Optional[dict] = None, validate: bool = True):
+    def __init__(self, url: str, metadata: dict | None = None, validate: bool = True):
         """Initialize the object.
 
         Args:
@@ -592,7 +589,7 @@ def __str__(self) -> str:
         """
         output = f"class: {type(self).__name__}\n"
         output += f"url: ({self._url})\n"
-        output += f"metadata({str(len(self.metadata))}): {ut.print_truncated_list(list(self.metadata.keys()), sep=' ', include_brackets=False, transform=lambda y: y)}\n"
+        output += f"metadata({len(self.metadata)!s}): {ut.print_truncated_list(list(self.metadata.keys()), sep=' ', include_brackets=False, transform=lambda y: y)}\n"
 
         return output
 
@@ -676,7 +673,7 @@ def _get_cached_path(self) -> Path:
                 # If download fails, remove incomplete cache file and re-raise
                 if cache_path.exists():
                     cache_path.unlink(missing_ok=True)
-                raise IOError(f"Failed to download image from {self._url}: {e}.") from e
+                raise OSError(f"Failed to download image from {self._url}: {e}.") from e
             except ValueError as e:
                 raise ValueError(f"Invalid URL for download {self._url}: {e}.") from e
         return cache_path
@@ -713,9 +710,9 @@ def img_source(self, as_path: bool = False) -> str:
 
 
 def construct_spatial_image_class(
-    x: Union[str, Path, Image.Image, np.ndarray, VirtualSpatialImage],
-    metadata: Optional[dict] = None,
-    is_url: Optional[bool] = None,
+    x: str | Path | Image.Image | np.ndarray | VirtualSpatialImage,
+    metadata: dict | None = None,
+    is_url: bool | None = None,
 ) -> VirtualSpatialImage:
     """Factory function to create appropriate SpatialImage object.