diff --git a/kazu/annotation/label_studio.py b/kazu/annotation/label_studio.py
index 546ed70e..fa71946f 100644
--- a/kazu/annotation/label_studio.py
+++ b/kazu/annotation/label_studio.py
@@ -147,14 +147,16 @@ def _create_mapping_region(
                 "start": span.start,
                 "end": span.end,
                 "text": match,
-                "taxonomy": sorted(
-                    set(
-                        (mapping.source, f"{mapping.default_label}|{mapping.idx}")
-                        for mapping in ent.mappings
+                "taxonomy": (
+                    sorted(
+                        set(
+                            (mapping.source, f"{mapping.default_label}|{mapping.idx}")
+                            for mapping in ent.mappings
+                        )
                     )
-                )
-                if len(ent.mappings) > 0
-                else [("None", "unmapped|unmapped")],
+                    if len(ent.mappings) > 0
+                    else [("None", "unmapped|unmapped")]
+                ),
             },
         }
 
@@ -286,7 +288,7 @@ def _create_non_contiguous_entities(self, region_id: str) -> Iterable[Entity]:
                     mappings=mappings,
                 )
 
-    def _create_contiguous_entity(self, label, region_id, span):
+    def _create_contiguous_entity(self, label: str, region_id: str, span: CharSpan) -> Entity:
         single_span = frozenset([span])
         mappings = deepcopy(self.id_to_mappings.get(region_id, set()))
         return Entity(
@@ -514,7 +516,7 @@ def project_id(self) -> int:
                     f"more than one project with name: {self.project_name} found in Label Studio"
                 )
 
-    def delete_project_if_exists(self):
+    def delete_project_if_exists(self) -> None:
         try:
             resp = requests.delete(
                 f"{self.url}/api/projects/{self.project_id}",
@@ -553,7 +555,7 @@ def update_view(self, view: LabelStudioAnnotationView, docs: list[Document]) ->
     def update_view(self, view: LabelStudioAnnotationView, docs: list[set[Document]]) -> None:
         pass
 
-    def update_view(self, view, docs):
+    def update_view(self, view, docs):  # type: ignore[no-untyped-def]
         """Update the view of a label studio project.
 
         :param view:
@@ -590,7 +592,7 @@ def update_tasks(self, docs: list[Document]) -> None:
     def update_tasks(self, docs: list[set[Document]]) -> None:
         pass
 
-    def update_tasks(self, docs):
+    def update_tasks(self, docs):  # type: ignore[no-untyped-def]
         """Add tasks to a label studio project.
 
         :param docs: either a list of kazu documents, or a list of a set of kazu
diff --git a/kazu/utils/utils.py b/kazu/utils/utils.py
index 8a26d743..13ef0c12 100644
--- a/kazu/utils/utils.py
+++ b/kazu/utils/utils.py
@@ -150,7 +150,9 @@ def _create_ngrams_iter(tokens: Sequence[str], n: int) -> Iterable[Sequence[str]
     pass
 
 
-def _create_ngrams_iter(tokens, n=2):
+def _create_ngrams_iter(
+    tokens: Union[str, Sequence[str]], n: int = 2
+) -> Union[Iterable[str], Iterable[Sequence[str]]]:
     """Yields ngrams of the input as a sequence of strings.
 
     Tokens can be a single string where each token is a character, or an Iterable of
@@ -182,13 +184,13 @@ def create_word_ngrams(s: str, n: int = 2) -> list[str]:
 class Singleton(type):
     _instances: dict[type, Any] = {}
 
-    def __call__(cls, *args, **kwargs):
+    def __call__(cls, *args: Any, **kwargs: Any) -> Any:
         if cls not in cls._instances:
             cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
         return cls._instances[cls]
 
     @staticmethod
-    def clear_all():
+    def clear_all() -> None:
         logger.warning(
             "When clearing singletons, check that instances of classes with metaclass=Singleton are "
             "not used as class fields, as this will cause unexpected behaviour. Also note that any existing "
diff --git a/pyproject.toml b/pyproject.toml
index 7eadb274..bc55fbbb 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -216,10 +216,8 @@ module = [
   "kazu.utils.build_and_test_model_packs", # 5
   "kazu.linking.sapbert.train",            # 4
   "kazu.annotation.acceptance_test",       # 4
-  "kazu.utils.utils",                      # 3
   "kazu.utils.spacy_pipeline",             # 2
   "kazu.distillation.tiny_transformers",   # 2
-  "kazu.annotation.label_studio",          # 2
   "kazu.distillation.metrics",             # 1
 ]
 # we had a bunch of these in the codebase before we moved to a 'strict' mypy config, and it was too many