diff --git a/src/audio_feeder/_compat.py b/src/audio_feeder/_compat.py
index 93df4f7..fa5db20 100644
--- a/src/audio_feeder/_compat.py
+++ b/src/audio_feeder/_compat.py
@@ -6,6 +6,6 @@
 try:
     from enum import StrEnum  # type: ignore[attr-defined]
 except ImportError:
-    from backports.strenum import StrEnum  # type: ignore[import]
+    from backports.strenum import StrEnum  # type: ignore[import,no-redef]
 
 __all__ = ("Self", "StrEnum")
diff --git a/src/audio_feeder/file_probe.py b/src/audio_feeder/file_probe.py
index 8d2e4f4..121937c 100644
--- a/src/audio_feeder/file_probe.py
+++ b/src/audio_feeder/file_probe.py
@@ -67,6 +67,7 @@ class OverdriveMediaMarker:
     @classmethod
     def from_xml(cls, xml: str) -> typing.Sequence[Self]:
         root = lxml.etree.fromstring(xml)
+        assert isinstance(root.tag, str)
         if root.tag != "Markers":
             raise ValueError(
                 f"Unknown media marker tag: {root.tag}. " + "Should be 'Markers'"
@@ -197,6 +198,7 @@ def from_json(cls, json_dict: FFProbeReturnJSON) -> Self:
             if omm_tag in format_info.tags:
                 omm_tags = OverdriveMediaMarker.from_xml(format_info.tags[omm_tag])
                 omm_tags = sorted(omm_tags)
+                assert format_info.duration is not None  # TODO: Handle this gracefully
 
                 for num, start_tag, end_tag in zip(
                     itertools.count(1),
diff --git a/src/audio_feeder/m4btools.py b/src/audio_feeder/m4btools.py
index 312ffc3..0b3173e 100644
--- a/src/audio_feeder/m4btools.py
+++ b/src/audio_feeder/m4btools.py
@@ -385,7 +385,9 @@ def chapter_split_jobs(
 
             job_pool.append(new_job)
 
-        if abs(chapter.end_time - file_infos[fpath].format_info.duration) < 0.25:
+        duration = file_infos[fpath].format_info.duration
+        assert duration is not None  # TODO: Handle this gracefully
+        if abs(chapter.end_time - duration) < 0.25:
             end_time = None
         else:
             end_time = chapter.end_time
diff --git a/src/audio_feeder/object_handler.py b/src/audio_feeder/object_handler.py
index 5fd2916..a004b36 100644
--- a/src/audio_feeder/object_handler.py
+++ b/src/audio_feeder/object_handler.py
@@ -50,16 +50,16 @@ class BaseObject:
     id: ID
 
     def to_dict(self) -> typing.Mapping[str, typing.Any]:
-        return attrs.asdict(self)
+        return attrs.asdict(self)  # type: ignore[arg-type]
 
     def to_dict_sparse(
         self, *, _filter=_filter_sparse
     ) -> typing.Mapping[str, typing.Any]:
-        return attrs.asdict(self, filter=_filter)
+        return attrs.asdict(self, filter=_filter)  # type: ignore[arg-type]
 
     def copy(self: Self) -> Self:
         """Make a new copy of this object."""
-        return attrs.evolve(self)
+        return attrs.evolve(self)  # type: ignore[misc]
 
 
 # SqlAlchemy has problems with slots ☹
diff --git a/src/audio_feeder/rss_feeds.py b/src/audio_feeder/rss_feeds.py
index 8e6c8b9..9d35de7 100644
--- a/src/audio_feeder/rss_feeds.py
+++ b/src/audio_feeder/rss_feeds.py
@@ -208,9 +208,10 @@ def _executor() -> futures.Executor:
             file_hash = None
 
         if entry_obj.file_metadata is None or m_rel_path not in entry_obj.file_metadata:
+            # TODO: Use an assertion or fix fl.path possibly being None
             metadata_futures.append(
                 _executor().submit(
-                    lambda fl, fh: (fl, fp.FileInfo.from_file(fl.path), fh),
+                    lambda fl, fh: (fl, fp.FileInfo.from_file(fl.path), fh),  # type: ignore[arg-type]
                     file_loc,
                     file_hash,
                 )
diff --git a/src/audio_feeder/sql_database_handler.py b/src/audio_feeder/sql_database_handler.py
index f5b5efa..15c47c6 100644
--- a/src/audio_feeder/sql_database_handler.py
+++ b/src/audio_feeder/sql_database_handler.py
@@ -11,6 +11,7 @@
 
 import attrs
 import sqlalchemy as sa
+import sqlalchemy.types
 from sqlalchemy import orm
 
 from . import _object_types as ot
diff --git a/src/audio_feeder/updater.py b/src/audio_feeder/updater.py
index 90d6f76..e81d62f 100644
--- a/src/audio_feeder/updater.py
+++ b/src/audio_feeder/updater.py
@@ -30,7 +30,7 @@
 # This technically violates PEP 484, but it works. See
 # https://github.com/python/mypy/issues/14023 for more details.
 _PBar = typing.TypeVar(
-    "_PBar", bound=typing.Callable[[typing.Iterable[_T]], typing.Iterable[_T]]
+    "_PBar", bound=typing.Callable[[typing.Iterable[_T]], typing.Iterable[_T]]  # type: ignore[valid-type]
 )
 
 
diff --git a/tox.ini b/tox.ini
index 766938b..31f9c99 100644
--- a/tox.ini
+++ b/tox.ini
@@ -85,7 +85,7 @@ description = Run typechecking
 deps =
     attrs
     click
-    mypy>=0.991,<1
+    mypy>=0.991
     types-requests
     types-lxml
     types-pyyaml