diff --git a/bookwyrm/templatetags/status_display.py b/bookwyrm/templatetags/status_display.py
index cf526c099..430fba198 100644
--- a/bookwyrm/templatetags/status_display.py
+++ b/bookwyrm/templatetags/status_display.py
@@ -1,4 +1,5 @@
 """ template filters """
+import datetime
 from typing import Any, Optional
 from dateutil.relativedelta import relativedelta
 from django import template
@@ -34,11 +35,13 @@ def get_replies(status: models.Status) -> Any:
 @register.filter(name="parent")
 def get_parent(status: models.Status) -> Any:
     """get the reply parent for a status"""
-    return (
-        models.Status.objects.filter(id=status.reply_parent_id)
-        .select_subclasses()
-        .first()
-    )
+    if status.reply_parent_id:
+        return (
+            models.Status.objects.filter(id=status.reply_parent_id)
+            .select_subclasses()
+            .first()
+        )
+    return None
 
 
 @register.filter(name="boosted_status")
@@ -53,7 +56,7 @@ def get_boosted(boost: models.Boost) -> Any:
 
 
 @register.filter(name="published_date")
-def get_published_date(date: str) -> Any:
+def get_published_date(date: datetime.datetime) -> str | None:
     """less verbose combo of humanize filters"""
     if not date:
         return ""
diff --git a/bookwyrm/templatetags/utilities.py b/bookwyrm/templatetags/utilities.py
index 0aabb94f7..f1f7c4bdd 100644
--- a/bookwyrm/templatetags/utilities.py
+++ b/bookwyrm/templatetags/utilities.py
@@ -93,7 +93,7 @@ def get_book_cover_thumbnail(
 
 
 @register.filter(name="get_isni_bio")
-def get_isni_bio(existing: int, author: Author) -> str:
+def get_isni_bio(existing: list[str], author: Author) -> str:
     """Returns the isni bio string if an existing author has an isni listed"""
     auth_isni = re.sub(r"\D", "", str(author.isni))
     if len(existing) == 0:
diff --git a/bookwyrm/utils/cache.py b/bookwyrm/utils/cache.py
index 5e896e621..df11f16de 100644
--- a/bookwyrm/utils/cache.py
+++ b/bookwyrm/utils/cache.py
@@ -1,17 +1,20 @@
 """ Custom handler for caching """
-from typing import Any, Callable, Tuple, Union
+from typing import Callable, Optional, ParamSpec, TypeVar, cast
 
 from django.core.cache import cache
 
+Args = ParamSpec("Args")
+Ret = TypeVar("Ret")
+
 
 def get_or_set(
     cache_key: str,
-    function: Callable[..., Any],
-    *args: Tuple[Any, ...],
-    timeout: Union[float, None] = None
-) -> Any:
+    function: Callable[Args, Ret],
+    *args: Args.args,
+    timeout: Optional[float] = None
+) -> Ret:
     """Django's built-in get_or_set isn't cutting it"""
-    value = cache.get(cache_key)
+    value = cast(Optional[Ret], cache.get(cache_key))
     if value is None:
         value = function(*args)
         cache.set(cache_key, value, timeout=timeout)
diff --git a/mypy.ini b/mypy.ini
index 567ca7d3f..ef5d2d78f 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -25,4 +25,4 @@ ignore_errors = False
 [mypy-bookwyrm.templatetags.*]
 ignore_errors = False
 allow_untyped_calls = True
-disable_error_code = attr-defined, arg-type, misc
+disable_error_code = attr-defined