diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 96ce5e7b..6b31f1c2 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -50,7 +50,9 @@ jobs:
       - name: Install cargo-fuzz
         run: |
           if ! command -v cargo-fuzz >/dev/null 2>&1; then
-            cargo +nightly install cargo-fuzz --locked
+            # cargo-fuzz's lockfile can lag nightly compatibility; fall back to
+            # unlocked dependency resolution when --locked fails.
+            cargo +nightly install cargo-fuzz --locked || cargo +nightly install cargo-fuzz
           fi
 
       - name: Cargo fuzz (${{ matrix.target }})
diff --git a/setup.py b/setup.py
index 10c12a10..1d165b63 100644
--- a/setup.py
+++ b/setup.py
@@ -2,13 +2,14 @@
 import platform
 import subprocess
 import sys
+from collections.abc import Callable
 from pathlib import Path
 
 from setuptools import Command, Extension, setup
 from setuptools.command.build import build
 from setuptools.command.build_ext import build_ext
 
-BUILD_HOOKS = []
+BUILD_HOOKS: list[Callable[..., None]] = []
 
 
 def add_build_hook(hook):