diff --git a/src/pydrex/io.py b/src/pydrex/io.py
index 244ad5aa..6f7b133b 100644
--- a/src/pydrex/io.py
+++ b/src/pydrex/io.py
@@ -425,7 +425,7 @@ def save_scsv(file, schema, data, **kwargs):
                             f"invalid data for column '{names[i]}'."
                             + f" Cannot parse {d} as type '{t.__qualname__}'."
                         ) from None
-                    if t == bool:
+                    if isinstance(t, bool):
                         row.append(d)
                     elif t in (float, complex):
                         if np.isnan(d) and np.isnan(t(f)):
@@ -747,7 +747,7 @@ def _parse_scsv_cell(func, data, missingstr=None, fillval=None):
         if fillval == "NaN":
             return func(np.nan)
         return func(fillval)
-    elif func == bool:
+    elif func.__qualname__ == "bool":
         return _parse_scsv_bool(data)
     return func(data.strip())
 
diff --git a/src/pydrex/mesh.py b/src/pydrex/mesh.py
index 9fca15dd..60a54abe 100644
--- a/src/pydrex/mesh.py
+++ b/src/pydrex/mesh.py
@@ -259,7 +259,7 @@ def rectangle(
 
     custom_constraints = kwargs.pop("custom_constraints", None)
     if custom_constraints is not None:
-        dummy_index = ({0, 1, 2} - set([h, v])).pop()
+        dummy_index = ({0, 1, 2} - {h, v}).pop()
         indices, constraints = custom_constraints
         point_constraints = np.insert(
             point_constraints,
diff --git a/tests/conftest.py b/tests/conftest.py
index cd3f0de9..479a23fc 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -159,7 +159,7 @@ def named_tempfile_kwargs(request):
     if sys.platform == "win32":
         return {"delete": False}
     else:
-        return dict()
+        return {}
 
 
 @pytest.fixture(scope="session")
diff --git a/tests/test_doctests.py b/tests/test_doctests.py
index 21c0c45c..04c9353f 100644
--- a/tests/test_doctests.py
+++ b/tests/test_doctests.py
@@ -57,12 +57,12 @@ def test_doctests(module, capsys, verbose):
             else:
                 lineno = f":{e.test.lineno + 1 + e.example.lineno}"
             err_type, err, _ = e.exc_info
-            if err_type == NameError:  # Raised on missing optional functions.
+            if err_type is NameError:  # Raised on missing optional functions.
                 # Issue warning but let the test suite pass.
                 _log.warning(
                     "skipping doctest of missing optional symbol in %s", module
                 )
-            elif err_type == np.core._exceptions._ArrayMemoryError:
+            elif err_type is np.core._exceptions._ArrayMemoryError:
                 # Faiures to allocate should not be fatal to the doctest test suite.
                 _log.warning(
                     "skipping doctests for module %s due to insufficient memory", module
diff --git a/tests/test_simple_shear_2d.py b/tests/test_simple_shear_2d.py
index f2763e44..7abc8bb1 100644
--- a/tests/test_simple_shear_2d.py
+++ b/tests/test_simple_shear_2d.py
@@ -2,7 +2,6 @@
 
 import contextlib as cl
 import functools as ft
-import sys
 from time import process_time
 
 import numpy as np
diff --git a/tests/test_simple_shear_3d.py b/tests/test_simple_shear_3d.py
index ddd32f67..5be8d304 100644
--- a/tests/test_simple_shear_3d.py
+++ b/tests/test_simple_shear_3d.py
@@ -19,9 +19,9 @@
 
 Pool, HAS_RAY = _utils.import_proc_pool()
 if HAS_RAY:
-    import ray
+    import ray  # noqa: F401
 
-    from pydrex import distributed as _dstr
+    from pydrex import distributed as _dstr  # noqa: F401
 
 # Subdirectory of `outdir` used to store outputs from these tests.
 SUBDIR = "3d_simple_shear"
@@ -192,7 +192,10 @@ def test_direction_change(
                         ]
                     )
                     olA_downsampled, _ = _stats.resample_orientations(
-                        olivine.orientations, olivine.fractions, seed=_seeds[s], n_samples=1000
+                        olivine.orientations,
+                        olivine.fractions,
+                        seed=_seeds[s],
+                        n_samples=1000,
                     )
                     olA_strength[s, :] = _diagnostics.misorientation_indices(
                         olA_downsampled, _geo.LatticeSystem.orthorhombic, pool=pool
@@ -223,7 +226,10 @@ def test_direction_change(
                         ]
                     )
                     ens_downsampled, _ = _stats.resample_orientations(
-                        enstatite.orientations, enstatite.fractions, seed=_seeds[s], n_samples=1000
+                        enstatite.orientations,
+                        enstatite.fractions,
+                        seed=_seeds[s],
+                        n_samples=1000,
                     )
                     ens_strength[s, :] = _diagnostics.misorientation_indices(
                         ens_downsampled, _geo.LatticeSystem.orthorhombic, pool=pool