diff --git a/kittens/diff/collect.py b/kittens/diff/collect.py
index 329833207..1f9808043 100644
--- a/kittens/diff/collect.py
+++ b/kittens/diff/collect.py
@@ -4,12 +4,13 @@
 
 import os
 import re
+from contextlib import suppress
 from functools import lru_cache
 from hashlib import md5
 from mimetypes import guess_type
-from contextlib import suppress
+from typing import Dict
 
-path_name_map = {}
+path_name_map: Dict[str, str] = {}
 
 
 class Segment:
@@ -146,13 +147,17 @@ def data_for_path(path):
     return ans
 
 
-@lru_cache(maxsize=1024)
-def lines_for_path(path):
-    data = data_for_path(path).replace('\t', lines_for_path.replace_tab_by)
-    return tuple(sanitize(data).splitlines())
+class LinesForPath:
+
+    replace_tab_by = ' ' * 4
+
+    @lru_cache(maxsize=1024)
+    def __call__(self, path):
+        data = data_for_path(path).replace('\t', self.replace_tab_by)
+        return tuple(sanitize(data).splitlines())
 
 
-lines_for_path.replace_tab_by = ' ' * 4
+lines_for_path = LinesForPath()
 
 
 @lru_cache(maxsize=1024)
diff --git a/kittens/diff/config_data.py b/kittens/diff/config_data.py
index 9bdbf3f60..502ed4a37 100644
--- a/kittens/diff/config_data.py
+++ b/kittens/diff/config_data.py
@@ -3,18 +3,17 @@
 # License: GPL v3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
 
 
+from functools import partial
 # Utils  {{{
 from gettext import gettext as _
-from functools import partial
+from typing import Dict, Union
 
-from kitty.conf.definition import option_func
-from kitty.conf.utils import (
-    positive_int, python_string, to_color
-)
+from kitty.conf.definition import Option, Shortcut, option_func
+from kitty.conf.utils import positive_int, python_string, to_color
 
 # }}}
 
-all_options = {}
+all_options: Dict[str, Union[Option, Shortcut]] = {}
 o, k, g, all_groups = option_func(all_options, {
     'colors': [_('Colors')],
     'diff': [_('Diffing'), ],
@@ -121,4 +120,4 @@ k('prev_match', '<', 'scroll_to prev-match', _('Scroll to previous search match'
 k('search_forward_simple', 'f', 'start_search substring forward', _('Search forward (no regex)'))
 k('search_backward_simple', 'b', 'start_search substring backward', _('Search backward (no regex)'))
 
-type_map = {o.name: o.option_type for o in all_options.values() if hasattr(o, 'option_type')}
+type_map = {o.name: o.option_type for o in all_options.values() if isinstance(o, Option)}
diff --git a/kittens/diff/diff_speedup.pyi b/kittens/diff/diff_speedup.pyi
new file mode 100644
index 000000000..9a7a0927d
--- /dev/null
+++ b/kittens/diff/diff_speedup.pyi
@@ -0,0 +1,14 @@
+from typing import List, Optional, Tuple
+
+from .collect import Segment
+
+
+def split_with_highlights(
+    line: str, truncate_points: List[int], fg_highlights: List,
+    bg_highlight: Optional[Segment]
+) -> List:
+    pass
+
+
+def changed_center(left_prefix: str, right_postfix: str) -> Tuple[int, int]:
+    pass
diff --git a/kittens/diff/highlight.py b/kittens/diff/highlight.py
index 2bd02c4c9..0de0e9b1a 100644
--- a/kittens/diff/highlight.py
+++ b/kittens/diff/highlight.py
@@ -6,10 +6,10 @@ import concurrent
 import os
 import re
 
-from pygments import highlight
-from pygments.formatter import Formatter
-from pygments.lexers import get_lexer_for_filename
-from pygments.util import ClassNotFound
+from pygments import highlight  # type: ignore
+from pygments.formatter import Formatter  # type: ignore
+from pygments.lexers import get_lexer_for_filename  # type: ignore
+from pygments.util import ClassNotFound  # type: ignore
 
 from kitty.rgb import color_as_sgr, parse_sharp
 
diff --git a/kittens/tui/operations.py b/kittens/tui/operations.py
index 5e711b344..8d7d6e4a3 100644
--- a/kittens/tui/operations.py
+++ b/kittens/tui/operations.py
@@ -71,7 +71,7 @@ def set_line_wrapping(yes_or_no: bool) -> str:
 
 
 def set_cursor_visible(yes_or_no: bool) -> str:
-    return set_mode('DECTEM') if yes_or_no else reset_mode('DECTCEM')
+    return set_mode('DECTCEM') if yes_or_no else reset_mode('DECTCEM')
 
 
 def set_cursor_position(x, y) -> str:  # (0, 0) is top left
diff --git a/kitty/fast_data_types.pyi b/kitty/fast_data_types.pyi
index 4c02b5990..d10cc8fda 100644
--- a/kitty/fast_data_types.pyi
+++ b/kitty/fast_data_types.pyi
@@ -719,6 +719,10 @@ def set_window_render_data(
     pass
 
 
+def truncate_point_for_length(text: str, num_cells: int, start_pos: int = 0) -> int:
+    pass
+
+
 class ChildMonitor:
 
     def __init__(
diff --git a/kitty/screen.c b/kitty/screen.c
index d5d5a4a4a..9cceb5c28 100644
--- a/kitty/screen.c
+++ b/kitty/screen.c
@@ -1866,7 +1866,7 @@ screen_wcswidth(PyObject UNUSED *self, PyObject *str) {
 static PyObject*
 screen_truncate_point_for_length(PyObject UNUSED *self, PyObject *args) {
     PyObject *str; unsigned int num_cells, start_pos = 0;
-    if (!PyArg_ParseTuple(args, "OI|I", &str, &num_cells, &start_pos)) return NULL;
+    if (!PyArg_ParseTuple(args, "UI|I", &str, &num_cells, &start_pos)) return NULL;
     if (PyUnicode_READY(str) != 0) return NULL;
     int kind = PyUnicode_KIND(str);
     void *data = PyUnicode_DATA(str);