diff --git a/src/sentry/api/endpoints/group_ai_autofix.py b/src/sentry/api/endpoints/group_ai_autofix.py
index 4adf59ceefc76d..9146861349be3f 100644
--- a/src/sentry/api/endpoints/group_ai_autofix.py
+++ b/src/sentry/api/endpoints/group_ai_autofix.py
@@ -48,7 +48,7 @@ class GroupAutofixEndpoint(GroupEndpoint):
     }
 
     def _get_serialized_event(
-        self, event_id: int, group: Group, user: AbstractBaseUser | AnonymousUser
+        self, event_id: str, group: Group, user: AbstractBaseUser | AnonymousUser
     ) -> dict[str, Any] | None:
         event = eventstore.backend.get_event_by_id(group.project.id, event_id, group_id=group.id)
 
diff --git a/src/sentry/eventstore/base.py b/src/sentry/eventstore/base.py
index 30a225256cddbb..7259e980acb680 100644
--- a/src/sentry/eventstore/base.py
+++ b/src/sentry/eventstore/base.py
@@ -226,12 +226,12 @@ def get_unfetched_events(
 
     def get_event_by_id(
         self,
-        project_id,
-        event_id,
-        group_id=None,
+        project_id: int,
+        event_id: str,
+        group_id: int | None = None,
         skip_transaction_groupevent=False,
         tenant_ids=None,
-        occurrence_id=None,
+        occurrence_id: str | None = None,
     ):
         """
         Gets a single event of any event type given a project_id and event_id.
diff --git a/src/sentry/eventstore/reprocessing/base.py b/src/sentry/eventstore/reprocessing/base.py
index 1a08cf194e9b5f..3d2dfe729035f2 100644
--- a/src/sentry/eventstore/reprocessing/base.py
+++ b/src/sentry/eventstore/reprocessing/base.py
@@ -45,7 +45,7 @@ def expire_hash(
         self,
         project_id: int,
         group_id: int,
-        event_id: int,
+        event_id: str,
         date_val: datetime,
         old_primary_hash: str,
     ) -> None:
diff --git a/src/sentry/eventstore/reprocessing/redis.py b/src/sentry/eventstore/reprocessing/redis.py
index eb907991e2ac25..fe19f191039939 100644
--- a/src/sentry/eventstore/reprocessing/redis.py
+++ b/src/sentry/eventstore/reprocessing/redis.py
@@ -93,7 +93,7 @@ def expire_hash(
         self,
         project_id: int,
         group_id: int,
-        event_id: int,
+        event_id: str,
         date_val: datetime,
         old_primary_hash: str,
     ) -> None:
diff --git a/src/sentry/eventstore/snuba/backend.py b/src/sentry/eventstore/snuba/backend.py
index 0fdc96c3061913..6b994253430ee6 100644
--- a/src/sentry/eventstore/snuba/backend.py
+++ b/src/sentry/eventstore/snuba/backend.py
@@ -299,9 +299,9 @@ def __get_events(
 
     def get_event_by_id(
         self,
-        project_id,
-        event_id,
-        group_id=None,
+        project_id: int,
+        event_id: str,
+        group_id: int | None = None,
         skip_transaction_groupevent=False,
         tenant_ids=None,
         occurrence_id: str | None = None,
diff --git a/src/sentry/issues/related/trace_connected.py b/src/sentry/issues/related/trace_connected.py
index 98c2ae098f1f56..86b3aede44effd 100644
--- a/src/sentry/issues/related/trace_connected.py
+++ b/src/sentry/issues/related/trace_connected.py
@@ -28,7 +28,7 @@ def trace_connected_analysis(
     if event_id:
         # If we are passing an specific event_id, we need to get the project_id
         assert project_id is not None
-        event = eventstore.backend.get_event_by_id(project_id, event_id, group_id=group.id)
+        event = eventstore.backend.get_event_by_id(int(project_id), event_id, group_id=group.id)
         # If we are requesting an specific event, we want to be notified with an error
         assert event is not None
         # This ensures that the event is actually part of the group and we are notified
diff --git a/src/sentry/reprocessing2.py b/src/sentry/reprocessing2.py
index 50f4f85b34edfe..e49082432061f2 100644
--- a/src/sentry/reprocessing2.py
+++ b/src/sentry/reprocessing2.py
@@ -315,7 +315,7 @@ def _send_delete_old_primary_hash_messages(
 def buffered_delete_old_primary_hash(
     project_id: int,
     group_id: int,
-    event_id: int | None = None,
+    event_id: str | None = None,
     datetime: datetime | None = None,
     old_primary_hash: str | None = None,
     current_primary_hash: str | None = None,
diff --git a/src/sentry/tasks/post_process.py b/src/sentry/tasks/post_process.py
index ab5183e3689427..a1d130381b7c33 100644
--- a/src/sentry/tasks/post_process.py
+++ b/src/sentry/tasks/post_process.py
@@ -512,7 +512,8 @@ def post_process_group(
     cache_key,
     group_id=None,
     occurrence_id: str | None = None,
-    project_id: int | None = None,
+    *,
+    project_id: int,
     **kwargs,
 ):
     """
diff --git a/tests/relay_integration/test_sdk.py b/tests/relay_integration/test_sdk.py
index a5f411743dded4..7a83ed6fc7a7c5 100644
--- a/tests/relay_integration/test_sdk.py
+++ b/tests/relay_integration/test_sdk.py
@@ -43,6 +43,7 @@ def post_event_with_sdk(settings, relay_server, wait_for_ingest_consumer):
 
     def inner(*args, **kwargs):
         event_id = sentry_sdk.capture_event(*args, **kwargs)
+        assert event_id is not None
         sentry_sdk.flush()
 
         with sentry_sdk.scope.use_scope(current_scope):