diff --git a/pygit2/_libgit2/ffi.pyi b/pygit2/_libgit2/ffi.pyi
index 0e865e31..08bc4196 100644
--- a/pygit2/_libgit2/ffi.pyi
+++ b/pygit2/_libgit2/ffi.pyi
@@ -329,6 +329,8 @@ def new(a: Literal['git_buf *'], b: tuple[NULL_TYPE, Literal[0]]) -> GitBufC: ..
 @overload
 def new(a: Literal['char **']) -> _Pointer[char_pointer]: ...
 @overload
+def new(a: Literal['void **'], b: bytes) -> _Pointer[bytes]: ...
+@overload
 def new(a: Literal['char[]', 'char []'], b: bytes | NULL_TYPE) -> ArrayC[char]: ...
 def addressof(a: object, attribute: str) -> _Pointer[object]: ...
 
diff --git a/pygit2/config.py b/pygit2/config.py
index 76d114fe..f05a8d13 100644
--- a/pygit2/config.py
+++ b/pygit2/config.py
@@ -110,7 +110,7 @@ def __del__(self) -> None:
         except AttributeError:
             pass
 
-    def _get(self, key: str | bytes) -> tuple[object, 'ConfigEntry']:
+    def _get(self, key: str | bytes) -> tuple[int, 'ConfigEntry']:
         key = str_to_bytes(key, 'key')
 
         entry = ffi.new('git_config_entry **')
diff --git a/pygit2/errors.py b/pygit2/errors.py
index 72a4af39..00108e32 100644
--- a/pygit2/errors.py
+++ b/pygit2/errors.py
@@ -32,7 +32,7 @@
 value_errors = set([C.GIT_EEXISTS, C.GIT_EINVALIDSPEC, C.GIT_EAMBIGUOUS])
 
 
-def check_error(err, io=False):
+def check_error(err: int, io=False) -> None:
     if err >= 0:
         return
 
diff --git a/pygit2/utils.py b/pygit2/utils.py
index b3d5d141..bdc6dfe4 100644
--- a/pygit2/utils.py
+++ b/pygit2/utils.py
@@ -93,7 +93,7 @@ def to_str(s):
     raise TypeError(f'unexpected type "{repr(s)}"')
 
 
-def ptr_to_bytes(ptr_cdata):
+def ptr_to_bytes(ptr_cdata) -> bytes:
     """
     Convert a pointer coming from C code (<cdata 'some_type *'>)
     to a byte buffer containing the address that the pointer refers to.