diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 4c065e2..7d16ee7 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
       - id: trailing-whitespace
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.15.20
+    rev: v0.16.1
     hooks:
       - id: ruff-check
         types_or: [python, pyproject]
diff --git a/_scripts/sync-releases.py b/_scripts/sync-releases.py
index 55f7069..d5836ce 100755
--- a/_scripts/sync-releases.py
+++ b/_scripts/sync-releases.py
@@ -65,6 +65,10 @@ class Docs:
 )
 
 
+class SyncReleasesException(Exception):
+    pass
+
+
 def api_request(endpoint: str) -> Any:
     resp = requests.get(
         f'https://api.github.com/{endpoint}',
@@ -105,7 +109,7 @@ def main() -> None:
         if version != prev['version']:
             cur = prev.copy()
             cur['version'] = version
-            cur['date'] = date.today().strftime('%Y-%m-%d')
+            cur['date'] = date.today().strftime('%Y-%m-%d')  # noqa: DTZ011
             releases[proj.id].insert(0, cur)
 
         # sync docs
@@ -130,7 +134,9 @@ def main() -> None:
             expected_hash = artifact['digest'].replace('sha256:', '')
             found_hash = sha256(resp.content).hexdigest()
             if expected_hash != found_hash:
-                raise Exception(f'SHA-256 {found_hash} != {expected_hash}')
+                raise SyncReleasesException(
+                    f'SHA-256 {found_hash} != {expected_hash}'
+                )
 
             # unpack
             docdir = DOCROOT / proj.docs.subdir
diff --git a/demo/_synctiles.py b/demo/_synctiles.py
index fe0f43c..d8ba884 100755
--- a/demo/_synctiles.py
+++ b/demo/_synctiles.py
@@ -213,6 +213,10 @@ class StatusMetadata(TypedDict):
     stamp: str | None
 
 
+class SyncTilesException(Exception):
+    pass
+
+
 def slugify(text: str) -> str:
     """Generate an ASCII-only slug."""
     text = normalize('NFKD', text.lower()).encode('ascii', 'ignore').decode()
@@ -450,7 +454,8 @@ def sync_slide(
     # Get current metadata
     try:
         resp = storage.object(metadata_key_name).get()
-        metadata: SlideMetadata | None = json.load(gzip.open(resp['Body']))
+        with gzip.open(resp['Body']) as body:
+            metadata: SlideMetadata | None = json.load(body)
     except storage.NoSuchKey:
         metadata = None
 
@@ -675,7 +680,8 @@ def start_retile(
     # If the stamp is changing, mark bucket dirty
     try:
         resp = storage.object(PurePath(METADATA_NAME)).get()
-        metadata: BucketMetadata = json.load(gzip.open(resp['Body']))
+        with gzip.open(resp['Body']) as body:
+            metadata: BucketMetadata = json.load(body)
         old_stamp = metadata['stamp']
     except storage.NoSuchKey:
         old_stamp = None
@@ -709,7 +715,7 @@ def retile_slide(
     # Tile slide
     slide_info = context['slides'].get(slide_relpath.as_posix())
     if slide_info is None:
-        raise Exception(f'No such slide {slide_relpath}')
+        raise SyncTilesException(f'No such slide {slide_relpath}')
     metadata = sync_slide(
         context['stamp'], storage, slide_relpath, slide_info, workers
     )
@@ -845,4 +851,4 @@ def finish_retile(ctxfile: TextIO, summarydir: Path) -> None:
     elif args.cmd == 'finish':
         finish_retile(args.context_file, args.summary_dir)
     else:
-        raise Exception('unimplemented subcommand')
+        raise SyncTilesException('unimplemented subcommand')