diff --git a/bin/update_iers_frozen b/bin/update_iers_frozen
index 25e088e..04bea48 100755
--- a/bin/update_iers_frozen
+++ b/bin/update_iers_frozen
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 """Update the iers_frozen file.
 """
-from importlib_resources import files
+from importlib.resources import files
 from desiutil.iers import update_iers
 
 frozen = str(files('desiutil') / 'data' / 'iers_frozen.ecsv')
diff --git a/py/desiutil/bitmask.py b/py/desiutil/bitmask.py
index 7fcaa9b..c76dfc6 100644
--- a/py/desiutil/bitmask.py
+++ b/py/desiutil/bitmask.py
@@ -236,6 +236,13 @@ def names(self, mask=None):
             for bitnum in sorted(bitnums):
                 names.append(self._bits[bitnum].name)
         else:
+            # The line below throws a lot of warnings:
+            # DeprecationWarning: Conversion of an array with ndim > 0 to a scalar is deprecated,
+            # and will error in future. Ensure you extract a single element from your array
+            # before performing this operation. (Deprecated NumPy 1.25.)
+            # It's not obvious where this is coming from though, since `mask`
+            # clearly should not be an array.
+            # https://github.com/numpy/numpy/issues/2955 was likely fixed in 2022.
             mask = int(mask)  # workaround numpy issue #2955 for uint64
             bitnum = 0
             while 2**bitnum <= mask:
diff --git a/py/desiutil/census.py b/py/desiutil/census.py
index 5829e2e..2382123 100644
--- a/py/desiutil/census.py
+++ b/py/desiutil/census.py
@@ -86,7 +86,7 @@ def get_options(test_args=None):
     from sys import argv
     from os.path import basename
     from argparse import ArgumentParser
-    from importlib_resources import files
+    from importlib.resources import files
     parser = ArgumentParser(description="Count number and size of DESI data files.",
                             prog=basename(argv[0]))
     parser.add_argument('-c', '--config-file', action='store', dest='config',
diff --git a/py/desiutil/install.py b/py/desiutil/install.py
index 437a787..3cc4249 100644
--- a/py/desiutil/install.py
+++ b/py/desiutil/install.py
@@ -16,7 +16,7 @@
 from io import BytesIO
 from subprocess import Popen, PIPE
 from types import MethodType
-from importlib_resources import files
+from importlib.resources import files
 from .git import last_tag
 from .log import get_logger, DEBUG, INFO
 from .modules import (init_modules, configure_module,
diff --git a/py/desiutil/modules.py b/py/desiutil/modules.py
index e83e3db..bceb683 100644
--- a/py/desiutil/modules.py
+++ b/py/desiutil/modules.py
@@ -16,7 +16,7 @@
 from shutil import which
 from stat import S_IRUSR, S_IRGRP, S_IROTH
 from configparser import ConfigParser
-from importlib_resources import files
+from importlib.resources import files
 from . import __version__ as desiutilVersion
 from .io import unlock_file
 from .log import log
diff --git a/py/desiutil/test/test_dust.py b/py/desiutil/test/test_dust.py
index b2c6940..371a490 100644
--- a/py/desiutil/test/test_dust.py
+++ b/py/desiutil/test/test_dust.py
@@ -12,7 +12,7 @@
 import numpy as np
 from .. import dust
 # import desiutil.dust as dust
-from importlib_resources import files
+from importlib.resources import files
 from astropy.coordinates import SkyCoord
 from astropy import units as u
 
diff --git a/py/desiutil/test/test_iers.py b/py/desiutil/test/test_iers.py
index b57fe49..cca5343 100644
--- a/py/desiutil/test/test_iers.py
+++ b/py/desiutil/test/test_iers.py
@@ -8,7 +8,7 @@
 import shutil
 import tempfile
 from unittest.mock import call, patch, MagicMock
-from importlib_resources import files
+from importlib.resources import files
 from astropy import __version__ as AstropyVersion
 import astropy.units as u
 import astropy.utils.iers
@@ -85,7 +85,7 @@ def test_update_iers_file(self, mock_logger):
     def test_update_iers(self, mock_logger, mock_iers, mock_time):
         """Test updating the IERS table.
         """
-        real_name = str(files('desiutil'), 'data' / 'iers_frozen.ecsv')
+        real_name = str(files('desiutil') / 'data' / 'iers_frozen.ecsv')
         t = QTable.read(real_name, format='ascii.ecsv')
         mock_iers.return_value = t
         d = MagicMock()
diff --git a/py/desiutil/test/test_install.py b/py/desiutil/test/test_install.py
index a4e81af..4d6f3e9 100644
--- a/py/desiutil/test/test_install.py
+++ b/py/desiutil/test/test_install.py
@@ -11,7 +11,7 @@
 from argparse import Namespace
 from tempfile import mkdtemp
 from logging import getLogger
-from importlib_resources import files
+from importlib.resources import files
 from ..log import DEBUG
 from ..install import DesiInstall, DesiInstallException, dependencies
 from .test_log import NullMemoryHandler
diff --git a/py/desiutil/test/test_modules.py b/py/desiutil/test/test_modules.py
index 83a7921..42f7eea 100644
--- a/py/desiutil/test/test_modules.py
+++ b/py/desiutil/test/test_modules.py
@@ -10,7 +10,7 @@
 from sys import version_info
 from shutil import rmtree
 from tempfile import mkdtemp
-from importlib_resources import files
+from importlib.resources import files
 from ..modules import (init_modules, configure_module, process_module,
                        default_module, _write_module_data)
 
diff --git a/py/desiutil/test/test_sklearn.py b/py/desiutil/test/test_sklearn.py
index da5fed2..11e4eef 100644
--- a/py/desiutil/test/test_sklearn.py
+++ b/py/desiutil/test/test_sklearn.py
@@ -4,7 +4,7 @@
 """
 import unittest
 from tempfile import NamedTemporaryFile
-from importlib_resources import files
+from importlib.resources import files
 import numpy as np
 from astropy.io import fits
 from ..sklearn import GaussianMixtureModel as GMM