diff --git a/mesonbuild/_typing.py b/mesonbuild/_typing.py
index 8336c46bd..2777d1983 100644
--- a/mesonbuild/_typing.py
+++ b/mesonbuild/_typing.py
@@ -43,27 +43,27 @@ class ImmutableListProtocol(Protocol[T]):
     def __iter__(self) -> typing.Iterator[T]: ...
 
     @typing.overload
-    def __getitem__(self, index: int) -> T: ...
+    def __getitem__(self, index: int, /) -> T: ...
     @typing.overload
-    def __getitem__(self, index: slice) -> typing.List[T]: ...
+    def __getitem__(self, index: slice, /) -> typing.List[T]: ...
 
-    def __contains__(self, item: T) -> bool: ...
+    def __contains__(self, item: T, /) -> bool: ...
 
     def __reversed__(self) -> typing.Iterator[T]: ...
 
     def __len__(self) -> int: ...
 
-    def __add__(self, other: typing.List[T]) -> typing.List[T]: ...
+    def __add__(self, other: typing.List[T], /) -> typing.List[T]: ...
 
-    def __eq__(self, other: typing.Any) -> bool: ...
-    def __ne__(self, other: typing.Any) -> bool: ...
-    def __le__(self, other: typing.Any) -> bool: ...
-    def __lt__(self, other: typing.Any) -> bool: ...
-    def __gt__(self, other: typing.Any) -> bool: ...
-    def __ge__(self, other: typing.Any) -> bool: ...
+    def __eq__(self, other: typing.Any, /) -> bool: ...
+    def __ne__(self, other: typing.Any, /) -> bool: ...
+    def __le__(self, other: typing.Any, /) -> bool: ...
+    def __lt__(self, other: typing.Any, /) -> bool: ...
+    def __gt__(self, other: typing.Any, /) -> bool: ...
+    def __ge__(self, other: typing.Any, /) -> bool: ...
 
-    def count(self, item: T) -> int: ...
+    def count(self, item: T, /) -> int: ...
 
-    def index(self, item: T) -> int: ...
+    def index(self, item: T, /) -> int: ...
 
     def copy(self) -> typing.List[T]: ...