diff --git a/src/caelestia/parser.py b/src/caelestia/parser.py
index 110e065..aafa852 100644
--- a/src/caelestia/parser.py
+++ b/src/caelestia/parser.py
@@ -6,7 +6,7 @@ from caelestia.utils.scheme import get_scheme_names, scheme_variants
 from caelestia.utils.wallpaper import get_wallpaper
 
 
-def parse_args() -> (argparse.ArgumentParser, argparse.Namespace):
+def parse_args() -> tuple[argparse.ArgumentParser, argparse.Namespace]:
     parser = argparse.ArgumentParser(prog="caelestia", description="Main control script for the Caelestia dotfiles")
     parser.add_argument("-v", "--version", action="store_true", help="print the current version")
 
diff --git a/src/caelestia/subcommands/screenshot.py b/src/caelestia/subcommands/screenshot.py
index 6b4c00a..9a8cd60 100644
--- a/src/caelestia/subcommands/screenshot.py
+++ b/src/caelestia/subcommands/screenshot.py
@@ -26,8 +26,11 @@ class Command:
         else:
             sc_data = subprocess.check_output(["grim", "-l", "0", "-g", self.args.region.strip(), "-"])
             swappy = subprocess.Popen(["swappy", "-f", "-"], stdin=subprocess.PIPE, start_new_session=True)
-            swappy.stdin.write(sc_data)
-            swappy.stdin.close()
+
+            # Ensure stdin is not None for the type checker
+            if swappy.stdin:
+                swappy.stdin.write(sc_data)
+                swappy.stdin.close()
 
     def fullscreen(self) -> None:
         sc_data = subprocess.check_output(["grim", "-"])
diff --git a/src/caelestia/subcommands/shell.py b/src/caelestia/subcommands/shell.py
index b9e81ed..48a71c2 100644
--- a/src/caelestia/subcommands/shell.py
+++ b/src/caelestia/subcommands/shell.py
@@ -33,11 +33,14 @@ class Command:
                 subprocess.run(args)
             else:
                 shell = subprocess.Popen(args, stdout=subprocess.PIPE, universal_newlines=True)
-                for line in shell.stdout:
-                    if self.filter_log(line):
-                        print(line, end="")
 
-    def shell(self, *args: list[str]) -> str:
+                # Ensure stdout is not None for the type checker
+                if shell.stdout:
+                    for line in shell.stdout:
+                        if self.filter_log(line):
+                            print(line, end="")
+
+    def shell(self, *args: str) -> str:
         return subprocess.check_output(["qs", "-c", "caelestia", *args], text=True)
 
     def filter_log(self, line: str) -> bool:
diff --git a/src/caelestia/subcommands/toggle.py b/src/caelestia/subcommands/toggle.py
index ba5a351..56565f3 100644
--- a/src/caelestia/subcommands/toggle.py
+++ b/src/caelestia/subcommands/toggle.py
@@ -3,6 +3,7 @@ import shlex
 import shutil
 from argparse import Namespace
 from collections import ChainMap
+from typing import Any, Callable, cast
 
 from caelestia.utils import hypr
 from caelestia.utils.paths import user_config_path
@@ -52,8 +53,8 @@ class DeepChainMap(ChainMap):
 
 class Command:
     args: Namespace
-    cfg: dict[str, dict[str, dict[str, any]]] | DeepChainMap
-    clients: list[dict[str, any]] = None
+    cfg: dict[str, dict[str, dict[str, Any]]] | DeepChainMap
+    clients: list[dict[str, Any]] | None = None
 
     def __init__(self, args: Namespace) -> None:
         self.args = args
@@ -120,27 +121,27 @@ class Command:
         if not spawned:
             hypr.dispatch("togglespecialworkspace", self.args.workspace)
 
-    def get_clients(self) -> list[dict[str, any]]:
+    def get_clients(self) -> list[dict[str, Any]]:
         if self.clients is None:
-            self.clients = hypr.message("clients")
-
+            self.clients = cast(list[dict[str, Any]], hypr.message("clients"))
         return self.clients
 
-    def move_client(self, selector: callable, workspace: str) -> None:
+    def move_client(self, selector: Callable, workspace: str) -> None:
         for client in self.get_clients():
             if selector(client) and client["workspace"]["name"] != f"special:{workspace}":
                 hypr.dispatch("movetoworkspacesilent", f"special:{workspace},address:{client['address']}")
 
-    def spawn_client(self, selector: callable, spawn: list[str]) -> bool:
+    def spawn_client(self, selector: Callable, spawn: list[str]) -> bool:
         if (spawn[0].endswith(".desktop") or shutil.which(spawn[0])) and not any(
             selector(client) for client in self.get_clients()
         ):
             hypr.dispatch("exec", f"[workspace special:{self.args.workspace}] app2unit -- {shlex.join(spawn)}")
             return True
-        return False
+        else:
+            return False
 
-    def handle_client_config(self, client: dict[str, any]) -> bool:
-        def selector(c: dict[str, any]) -> bool:
+    def handle_client_config(self, client: dict[str, Any]) -> bool:
+        def selector(c: dict[str, Any]) -> bool:
             # Each match is or, inside matches is and
             for match in client["match"]:
                 if is_subset(c, match):
@@ -156,5 +157,8 @@ class Command:
         return spawned
 
     def specialws(self) -> None:
-        special = next(m for m in hypr.message("monitors") if m["focused"])["specialWorkspace"]["name"]
-        hypr.dispatch("togglespecialworkspace", special[8:] or "special")
+        monitors = cast(list[dict[str, Any]], hypr.message("monitors"))
+        target = next((m for m in monitors if m.get("focused")), None)
+        if target:
+            special = target.get("specialWorkspace", {}).get("name", "")[8:] or "special"
+            hypr.dispatch("togglespecialworkspace", special)
diff --git a/src/caelestia/utils/colourfulness.py b/src/caelestia/utils/colourfulness.py
index f76c1b6..5e06eb3 100644
--- a/src/caelestia/utils/colourfulness.py
+++ b/src/caelestia/utils/colourfulness.py
@@ -11,8 +11,7 @@ def stddev(values: list[float], mean_val: float) -> float:
     return math.sqrt(sum((x - mean_val) ** 2 for x in values) / len(values)) if values else 0
 
 
-def calc_colourfulness(image: Image) -> float:
-    width, height = image.size
+def calc_colourfulness(image: Image.Image) -> float:
     pixels = list(image.getdata())  # List of (R, G, B) tuples
 
     rg_diffs = []
@@ -32,7 +31,7 @@ def calc_colourfulness(image: Image) -> float:
     return math.sqrt(std_rg**2 + std_yb**2) + 0.3 * math.sqrt(mean_rg**2 + mean_yb**2)
 
 
-def get_variant(image: Image) -> str:
+def get_variant(image: Image.Image) -> str:
     colourfulness = calc_colourfulness(image)
 
     if colourfulness < 10:
diff --git a/src/caelestia/utils/hypr.py b/src/caelestia/utils/hypr.py
index 81bc123..d251b98 100644
--- a/src/caelestia/utils/hypr.py
+++ b/src/caelestia/utils/hypr.py
@@ -1,17 +1,18 @@
-import json as j
+import json
 import os
 import socket
+from typing import Any
 
 socket_base = f"{os.getenv('XDG_RUNTIME_DIR')}/hypr/{os.getenv('HYPRLAND_INSTANCE_SIGNATURE')}"
 socket_path = f"{socket_base}/.socket.sock"
 socket2_path = f"{socket_base}/.socket2.sock"
 
 
-def message(msg: str, json: bool = True) -> str | dict[str, any]:
+def message(msg: str, is_json: bool = True) -> str | dict[str, Any]:
     with socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) as sock:
         sock.connect(socket_path)
 
-        if json:
+        if is_json:
             msg = f"j/{msg}"
         sock.send(msg.encode())
 
@@ -22,14 +23,17 @@ def message(msg: str, json: bool = True) -> str | dict[str, any]:
                 break
             resp += new_resp.decode()
 
-        return j.loads(resp) if json else resp
+        return json.loads(resp) if is_json else resp
 
 
-def dispatch(dispatcher: str, *args: list[any]) -> bool:
-    return message(f"dispatch {dispatcher} {' '.join(map(str, args))}".rstrip(), json=False) == "ok"
+def dispatch(dispatcher: str, *args: str) -> bool:
+    return message(f"dispatch {dispatcher} {' '.join(map(str, args))}".rstrip(), is_json=False) == "ok"
 
 
-def batch(*msgs: list[str], json: bool = False) -> str | dict[str, any]:
-    if json:
-        msgs = (f"j/{m.strip()}" for m in msgs)
-    return message(f"[[BATCH]]{';'.join(msgs)}", json=False)
+def batch(*msgs: str, is_json: bool = False) -> str | dict[str, Any]:
+    formatted_msgs = msgs
+
+    if is_json:
+        formatted_msgs = [f"j/{m.strip()}" for m in msgs]
+
+    return message(f"[[BATCH]]{';'.join(formatted_msgs)}", is_json=False)
diff --git a/src/caelestia/utils/material/generator.py b/src/caelestia/utils/material/generator.py
index 384fdd1..cf241e9 100644
--- a/src/caelestia/utils/material/generator.py
+++ b/src/caelestia/utils/material/generator.py
@@ -11,6 +11,14 @@ from materialyoucolor.scheme.scheme_rainbow import SchemeRainbow
 from materialyoucolor.scheme.scheme_tonal_spot import SchemeTonalSpot
 from materialyoucolor.scheme.scheme_vibrant import SchemeVibrant
 from materialyoucolor.utils.math_utils import difference_degrees, rotation_direction, sanitize_degrees_double
+from typing import Protocol, Any
+
+
+# The base DynamicScheme class requires a 'variant' argument, but the specific
+# subclasses in get_scheme() handle that internally. This Protocol tells the type
+# checker to expect our specific 3-argument setup instead of the base class signature.
+class SchemeConstructor(Protocol):
+    def __call__(self, source_color_hct: Any, is_dark: bool, contrast_level: float) -> DynamicScheme: ...
 
 try:
     from materialyoucolor.dynamiccolor.dynamic_scheme import DynamicScheme
@@ -147,7 +155,7 @@ def darken(colour: Hct, amount: float) -> Hct:
     return Hct.from_hct(colour.hue, colour.chroma - diff / 5, colour.tone - diff)
 
 
-def get_scheme(scheme: str) -> DynamicScheme:
+def get_scheme(scheme: str) -> SchemeConstructor:
     if scheme == "content":
         return SchemeContent
     if scheme == "expressive":
@@ -168,12 +176,12 @@ def get_scheme(scheme: str) -> DynamicScheme:
 
 
 def gen_scheme(scheme, primary: Hct) -> dict[str, str]:
-    light = scheme.mode == "light"
+    is_light = scheme.mode == "light"
 
     colours = {}
 
     # Material colours
-    primary_scheme = get_scheme(scheme.variant)(primary, not light, 0)
+    primary_scheme = get_scheme(scheme.variant)(source_color_hct=primary, is_dark=not is_light, contrast_level=0.0)
     if hasattr(MaterialDynamicColors, "all_colors"):  # materialyoucolor-python >= 3.0.0
         dyn_colours = MaterialDynamicColors()
         for colour in dyn_colours.all_colors:
@@ -191,28 +199,28 @@ def gen_scheme(scheme, primary: Hct) -> dict[str, str]:
         colours["neutral_variant_paletteKeyColor"] = colours["neutralVariantPaletteKeyColor"]
 
     # Harmonize terminal colours
-    for i, hct in enumerate(light_gruvbox if light else dark_gruvbox):
+    for i, hct in enumerate(light_gruvbox if is_light else dark_gruvbox):
         if scheme.variant == "monochrome":
-            colours[f"term{i}"] = grayscale(hct, light)
+            colours[f"term{i}"] = grayscale(hct, is_light)
         else:
             colours[f"term{i}"] = harmonize(
-                hct, colours["primary_paletteKeyColor"], (0.35 if i < 8 else 0.2) * (-1 if light else 1)
+                hct, colours["primary_paletteKeyColor"], (0.35 if i < 8 else 0.2) * (-1 if is_light else 1)
             )
 
     # Harmonize named colours
-    for i, hct in enumerate(light_catppuccin if light else dark_catppuccin):
+    for i, hct in enumerate(light_catppuccin if is_light else dark_catppuccin):
         if scheme.variant == "monochrome":
-            colours[colour_names[i]] = grayscale(hct, light)
+            colours[colour_names[i]] = grayscale(hct, is_light)
         else:
-            colours[colour_names[i]] = harmonize(hct, colours["primary_paletteKeyColor"], (-0.2 if light else 0.05))
+            colours[colour_names[i]] = harmonize(hct, colours["primary_paletteKeyColor"], (-0.2 if is_light else 0.05))
 
     # KColours
     for colour in kcolours:
         colours[colour["name"]] = harmonize(colour["hct"], colours["primary"], 0.1)
         colours[f"{colour['name']}Selection"] = harmonize(colour["hct"], colours["onPrimaryFixedVariant"], 0.1)
         if scheme.variant == "monochrome":
-            colours[colour["name"]] = grayscale(colours[colour["name"]], light)
-            colours[f"{colour['name']}Selection"] = grayscale(colours[f"{colour['name']}Selection"], light)
+            colours[colour["name"]] = grayscale(colours[colour["name"]], is_light)
+            colours[f"{colour['name']}Selection"] = grayscale(colours[f"{colour['name']}Selection"], is_light)
 
     if scheme.variant == "neutral":
         for name, hct in colours.items():
@@ -221,8 +229,8 @@ def gen_scheme(scheme, primary: Hct) -> dict[str, str]:
     # Darken surfaces for hard flavour
     if scheme.flavour == "hard":
         for colour in "background", *(k for k in colours.keys() if k.startswith("surface")):
-            colours[colour] = lighten(colours[colour], 0.4) if light else darken(colours[colour], 0.8)
-        colours["term0"] = lighten(colours["term0"], 0.4) if light else darken(colours["term0"], 0.9)
+            colours[colour] = lighten(colours[colour], 0.4) if is_light else darken(colours[colour], 0.8)
+        colours["term0"] = lighten(colours["term0"], 0.4) if is_light else darken(colours["term0"], 0.9)
 
     # FIXME: deprecated stuff
     colours["text"] = colours["onBackground"]
@@ -241,13 +249,13 @@ def gen_scheme(scheme, primary: Hct) -> dict[str, str]:
     # More darkening if hard flavour
     if scheme.flavour == "hard":
         for colour in "base", "mantle", "crust":
-            colours[colour] = lighten(colours[colour], 0.4) if light else darken(colours[colour], 0.9)
+            colours[colour] = lighten(colours[colour], 0.4) if is_light else darken(colours[colour], 0.9)
         for i in range(3):
             colours[f"overlay{i}"] = (
-                lighten(colours[f"overlay{i}"], 0.4) if light else darken(colours[f"overlay{i}"], 0.8)
+                lighten(colours[f"overlay{i}"], 0.4) if is_light else darken(colours[f"overlay{i}"], 0.8)
             )
             colours[f"surface{i}"] = (
-                lighten(colours[f"surface{i}"], 0.4) if light else darken(colours[f"surface{i}"], 0.8)
+                lighten(colours[f"surface{i}"], 0.4) if is_light else darken(colours[f"surface{i}"], 0.8)
             )
 
     # For debugging
@@ -256,7 +264,7 @@ def gen_scheme(scheme, primary: Hct) -> dict[str, str]:
     colours = {k: hex(v.to_int())[4:] for k, v in colours.items()}
 
     # Extended material
-    if light:
+    if is_light:
         colours["success"] = "4F6354"
         colours["onSuccess"] = "FFFFFF"
         colours["successContainer"] = "D1E8D5"
diff --git a/src/caelestia/utils/notify.py b/src/caelestia/utils/notify.py
index ee86236..c88dece 100644
--- a/src/caelestia/utils/notify.py
+++ b/src/caelestia/utils/notify.py
@@ -1,7 +1,7 @@
 import subprocess
 
 
-def notify(*args: list[str]) -> str:
+def notify(*args: str) -> str:
     return subprocess.check_output(["notify-send", "-a", "caelestia-cli", *args], text=True).strip()
 
 
diff --git a/src/caelestia/utils/paths.py b/src/caelestia/utils/paths.py
index 14eb550..3223b90 100644
--- a/src/caelestia/utils/paths.py
+++ b/src/caelestia/utils/paths.py
@@ -4,41 +4,42 @@ import os
 import shutil
 import tempfile
 from pathlib import Path
+from typing import Any
 
-config_dir = Path(os.getenv("XDG_CONFIG_HOME", Path.home() / ".config"))
-data_dir = Path(os.getenv("XDG_DATA_HOME", Path.home() / ".local/share"))
-state_dir = Path(os.getenv("XDG_STATE_HOME", Path.home() / ".local/state"))
-cache_dir = Path(os.getenv("XDG_CACHE_HOME", Path.home() / ".cache"))
-pictures_dir = Path(os.getenv("XDG_PICTURES_DIR", Path.home() / "Pictures"))
-videos_dir = Path(os.getenv("XDG_VIDEOS_DIR", Path.home() / "Videos"))
+config_dir: Path = Path(os.getenv("XDG_CONFIG_HOME", Path.home() / ".config"))
+data_dir: Path = Path(os.getenv("XDG_DATA_HOME", Path.home() / ".local/share"))
+state_dir: Path = Path(os.getenv("XDG_STATE_HOME", Path.home() / ".local/state"))
+cache_dir: Path = Path(os.getenv("XDG_CACHE_HOME", Path.home() / ".cache"))
+pictures_dir: Path = Path(os.getenv("XDG_PICTURES_DIR", Path.home() / "Pictures"))
+videos_dir: Path = Path(os.getenv("XDG_VIDEOS_DIR", Path.home() / "Videos"))
 
-c_config_dir = config_dir / "caelestia"
-c_data_dir = data_dir / "caelestia"
-c_state_dir = state_dir / "caelestia"
-c_cache_dir = cache_dir / "caelestia"
+c_config_dir: Path = config_dir / "caelestia"
+c_data_dir: Path = data_dir / "caelestia"
+c_state_dir: Path = state_dir / "caelestia"
+c_cache_dir: Path = cache_dir / "caelestia"
 
-user_config_path = c_config_dir / "cli.json"
-cli_data_dir = Path(__file__).parent.parent / "data"
-templates_dir = cli_data_dir / "templates"
-user_templates_dir = c_config_dir / "templates"
-theme_dir = c_state_dir / "theme"
+user_config_path: Path = c_config_dir / "cli.json"
+cli_data_dir: Path = Path(__file__).parent.parent / "data"
+templates_dir: Path = cli_data_dir / "templates"
+user_templates_dir: Path = c_config_dir / "templates"
+theme_dir: Path = c_state_dir / "theme"
 
-scheme_path = c_state_dir / "scheme.json"
-scheme_data_dir = cli_data_dir / "schemes"
-scheme_cache_dir = c_cache_dir / "schemes"
+scheme_path: Path = c_state_dir / "scheme.json"
+scheme_data_dir: Path = cli_data_dir / "schemes"
+scheme_cache_dir: Path = c_cache_dir / "schemes"
 
-wallpapers_dir = os.getenv("CAELESTIA_WALLPAPERS_DIR", pictures_dir / "Wallpapers")
-wallpaper_path_path = c_state_dir / "wallpaper/path.txt"
-wallpaper_link_path = c_state_dir / "wallpaper/current"
-wallpaper_thumbnail_path = c_state_dir / "wallpaper/thumbnail.jpg"
-wallpapers_cache_dir = c_cache_dir / "wallpapers"
+wallpapers_dir: Path = Path(os.getenv("CAELESTIA_WALLPAPERS_DIR", pictures_dir / "Wallpapers"))
+wallpaper_path_path: Path = c_state_dir / "wallpaper/path.txt"
+wallpaper_link_path: Path = c_state_dir / "wallpaper/current"
+wallpaper_thumbnail_path: Path = c_state_dir / "wallpaper/thumbnail.jpg"
+wallpapers_cache_dir: Path = c_cache_dir / "wallpapers"
 
-screenshots_dir = os.getenv("CAELESTIA_SCREENSHOTS_DIR", pictures_dir / "Screenshots")
-screenshots_cache_dir = c_cache_dir / "screenshots"
+screenshots_dir: Path = Path(os.getenv("CAELESTIA_SCREENSHOTS_DIR", pictures_dir / "Screenshots"))
+screenshots_cache_dir: Path = c_cache_dir / "screenshots"
 
-recordings_dir = os.getenv("CAELESTIA_RECORDINGS_DIR", videos_dir / "Recordings")
-recording_path = c_state_dir / "record/recording.mp4"
-recording_notif_path = c_state_dir / "record/notifid.txt"
+recordings_dir: Path = Path(os.getenv("CAELESTIA_RECORDINGS_DIR", videos_dir / "Recordings"))
+recording_path: Path = c_state_dir / "record/recording.mp4"
+recording_notif_path: Path = c_state_dir / "record/notifid.txt"
 
 
 def compute_hash(path: Path | str) -> str:
@@ -51,7 +52,7 @@ def compute_hash(path: Path | str) -> str:
     return sha.hexdigest()
 
 
-def atomic_dump(path: Path, content: dict[str, any]) -> None:
+def atomic_dump(path: Path, content: dict[str, Any]) -> None:
     with tempfile.NamedTemporaryFile("w") as f:
         json.dump(content, f)
         f.flush()
diff --git a/src/caelestia/utils/scheme.py b/src/caelestia/utils/scheme.py
index 57a5e0b..e08d777 100644
--- a/src/caelestia/utils/scheme.py
+++ b/src/caelestia/utils/scheme.py
@@ -1,6 +1,7 @@
 import json
 import random
 from pathlib import Path
+from typing import Any
 
 from caelestia.utils.notify import notify
 from caelestia.utils.paths import atomic_dump, scheme_data_dir, scheme_path
@@ -14,19 +15,19 @@ class Scheme:
     _colours: dict[str, str]
     notify: bool
 
-    def __init__(self, json: dict[str, any] | None) -> None:
-        if json is None:
+    def __init__(self, scheme_json: dict[str, Any] | None) -> None:
+        if scheme_json is None:
             self._name = "catppuccin"
             self._flavour = "mocha"
             self._mode = "dark"
             self._variant = "tonalspot"
             self._colours = read_colours_from_file(self.get_colours_path())
         else:
-            self._name = json["name"]
-            self._flavour = json["flavour"]
-            self._mode = json["mode"]
-            self._variant = json["variant"]
-            self._colours = json["colours"]
+            self._name = scheme_json["name"]
+            self._flavour = scheme_json["flavour"]
+            self._mode = scheme_json["mode"]
+            self._variant = scheme_json["variant"]
+            self._colours = scheme_json["colours"]
         self.notify = False
 
     @property
@@ -196,7 +197,7 @@ scheme_variants = [
     "content",
 ]
 
-scheme: Scheme = None
+scheme: Scheme | None = None
 
 
 def read_colours_from_file(path: Path) -> dict[str, str]:
@@ -225,7 +226,7 @@ def get_scheme_names() -> list[str]:
     return [*(f.name for f in scheme_data_dir.iterdir() if f.is_dir()), "dynamic"]
 
 
-def get_scheme_flavours(name: str = None) -> list[str]:
+def get_scheme_flavours(name: str | None = None) -> list[str]:
     if name is None:
         name = get_scheme().name
 
@@ -234,11 +235,11 @@ def get_scheme_flavours(name: str = None) -> list[str]:
     )
 
 
-def get_scheme_modes(name: str = None, flavour: str = None) -> list[str]:
-    if name is None:
+def get_scheme_modes(name: str | None = None, flavour: str | None = None) -> list[str]:
+    if name is None or flavour is None:
         scheme = get_scheme()
-        name = scheme.name
-        flavour = scheme.flavour
+        name = name or scheme.name
+        flavour = flavour or scheme.flavour
 
     if name == "dynamic":
         return ["light", "dark"]
diff --git a/src/caelestia/utils/theme.py b/src/caelestia/utils/theme.py
index c5ced3a..30e73f8 100644
--- a/src/caelestia/utils/theme.py
+++ b/src/caelestia/utils/theme.py
@@ -4,6 +4,8 @@ import re
 import shutil
 import subprocess
 import tempfile
+import shutil
+import fcntl
 from pathlib import Path
 
 from caelestia.utils.colour import get_dynamic_colours
@@ -34,10 +36,10 @@ def gen_scss(colours: dict[str, str]) -> str:
 
 
 def gen_replace(colours: dict[str, str], template: Path, hash: bool = False) -> str:
-    template = template.read_text()
+    new_template = template.read_text()
     for name, colour in colours.items():
-        template = template.replace(f"{{{{ ${name} }}}}", f"#{colour}" if hash else colour)
-    return template
+        new_template = new_template.replace(f"{{{{ ${name} }}}}", f"#{colour}" if hash else colour)
+    return new_template
 
 
 def gen_replace_dynamic(colours: dict[str, str], template: Path, mode: str) -> str:
@@ -65,7 +67,7 @@ def gen_replace_dynamic(colours: dict[str, str], template: Path, mode: str) -> s
     return template_filled
 
 
-def c2s(c: str, *i: list[int]) -> str:
+def hex_to_ansi(c: str, *i: int) -> str:
     """Hex to ANSI sequence (e.g. ffffff, 11 -> \x1b]11;rgb:ff/ff/ff\x1b\\)"""
     return f"\x1b]{';'.join(map(str, i))};rgb:{c[0:2]}/{c[2:4]}/{c[4:6]}\x1b\\"
 
@@ -82,29 +84,29 @@ def gen_sequences(colours: dict[str, str]) -> str:
         16+: 256 colours
     """
     return (
-        c2s(colours["onSurface"], 10)
-        + c2s(colours["surface"], 11)
-        + c2s(colours["secondary"], 12)
-        + c2s(colours["secondary"], 17)
-        + c2s(colours["term0"], 4, 0)
-        + c2s(colours["term1"], 4, 1)
-        + c2s(colours["term2"], 4, 2)
-        + c2s(colours["term3"], 4, 3)
-        + c2s(colours["term4"], 4, 4)
-        + c2s(colours["term5"], 4, 5)
-        + c2s(colours["term6"], 4, 6)
-        + c2s(colours["term7"], 4, 7)
-        + c2s(colours["term8"], 4, 8)
-        + c2s(colours["term9"], 4, 9)
-        + c2s(colours["term10"], 4, 10)
-        + c2s(colours["term11"], 4, 11)
-        + c2s(colours["term12"], 4, 12)
-        + c2s(colours["term13"], 4, 13)
-        + c2s(colours["term14"], 4, 14)
-        + c2s(colours["term15"], 4, 15)
-        + c2s(colours["primary"], 4, 16)
-        + c2s(colours["secondary"], 4, 17)
-        + c2s(colours["tertiary"], 4, 18)
+        hex_to_ansi(colours["onSurface"], 10)
+        + hex_to_ansi(colours["surface"], 11)
+        + hex_to_ansi(colours["secondary"], 12)
+        + hex_to_ansi(colours["secondary"], 17)
+        + hex_to_ansi(colours["term0"], 4, 0)
+        + hex_to_ansi(colours["term1"], 4, 1)
+        + hex_to_ansi(colours["term2"], 4, 2)
+        + hex_to_ansi(colours["term3"], 4, 3)
+        + hex_to_ansi(colours["term4"], 4, 4)
+        + hex_to_ansi(colours["term5"], 4, 5)
+        + hex_to_ansi(colours["term6"], 4, 6)
+        + hex_to_ansi(colours["term7"], 4, 7)
+        + hex_to_ansi(colours["term8"], 4, 8)
+        + hex_to_ansi(colours["term9"], 4, 9)
+        + hex_to_ansi(colours["term10"], 4, 10)
+        + hex_to_ansi(colours["term11"], 4, 11)
+        + hex_to_ansi(colours["term12"], 4, 12)
+        + hex_to_ansi(colours["term13"], 4, 13)
+        + hex_to_ansi(colours["term14"], 4, 14)
+        + hex_to_ansi(colours["term15"], 4, 15)
+        + hex_to_ansi(colours["primary"], 4, 16)
+        + hex_to_ansi(colours["secondary"], 4, 17)
+        + hex_to_ansi(colours["tertiary"], 4, 18)
     )
 
 
diff --git a/src/caelestia/utils/wallpaper.py b/src/caelestia/utils/wallpaper.py
index 77dcb38..02d3f4e 100644
--- a/src/caelestia/utils/wallpaper.py
+++ b/src/caelestia/utils/wallpaper.py
@@ -2,8 +2,10 @@ import json
 import os
 import random
 import subprocess
+
 from argparse import Namespace
 from pathlib import Path
+from typing import cast
 
 from materialyoucolor.hct import Hct
 from materialyoucolor.utils.color_utils import argb_from_rgb
@@ -11,6 +13,7 @@ from PIL import Image
 
 from caelestia.utils.hypr import message
 from caelestia.utils.material import get_colours_for_image
+from caelestia.utils.colourfulness import get_variant
 from caelestia.utils.paths import (
     compute_hash,
     user_config_path,
@@ -33,7 +36,7 @@ def check_wall(wall: Path, filter_size: tuple[int, int], threshold: float) -> bo
         return width >= filter_size[0] * threshold and height >= filter_size[1] * threshold
 
 
-def get_wallpaper() -> str:
+def get_wallpaper() -> str | None:
     try:
         return wallpaper_path_path.read_text()
     except IOError:
@@ -41,16 +44,16 @@ def get_wallpaper() -> str:
 
 
 def get_wallpapers(args: Namespace) -> list[Path]:
-    dir = Path(args.random)
-    if not dir.is_dir():
+    directory = Path(args.random)
+    if not directory.is_dir():
         return []
 
-    walls = [f for f in dir.rglob("*") if is_valid_image(f)]
+    walls = [f for f in directory.rglob("*") if is_valid_image(f)]
 
     if args.no_filter:
         return walls
 
-    monitors = message("monitors")
+    monitors = cast(list[dict[str, int]], message("monitors"))
     filter_size = min(m["width"] for m in monitors), min(m["height"] for m in monitors)
 
     return [f for f in walls if check_wall(f, filter_size, args.threshold)]
@@ -62,14 +65,14 @@ def get_thumb(wall: Path, cache: Path) -> Path:
     if not thumb.exists():
         with Image.open(wall) as img:
             img = img.convert("RGB")
-            img.thumbnail((128, 128), Image.NEAREST)
+            img.thumbnail((128, 128), Image.Resampling.NEAREST)
             thumb.parent.mkdir(parents=True, exist_ok=True)
             img.save(thumb, "JPEG")
 
     return thumb
 
 
-def get_smart_opts(wall: Path, cache: Path) -> str:
+def get_smart_opts(wall: Path, cache: Path) -> dict:
     opts_cache = cache / "smart.json"
 
     try:
@@ -77,15 +80,16 @@ def get_smart_opts(wall: Path, cache: Path) -> str:
     except (IOError, json.JSONDecodeError):
         pass
 
-    from caelestia.utils.colourfulness import get_variant
-
     opts = {}
 
     with Image.open(get_thumb(wall, cache)) as img:
         opts["variant"] = get_variant(img)
+        img.thumbnail((1, 1), Image.Resampling.LANCZOS)
+
+        # Cast the pixel to a tuple of 3 integers to safely unpack it
+        pixel = cast(tuple[int, int, int], img.getpixel((0, 0)))
+        hct = Hct.from_int(argb_from_rgb(*pixel))
 
-        img.thumbnail((1, 1), Image.LANCZOS)
-        hct = Hct.from_int(argb_from_rgb(*img.getpixel((0, 0))))
         opts["mode"] = "light" if hct.tone > 60 else "dark"
 
     opts_cache.parent.mkdir(parents=True, exist_ok=True)
@@ -144,7 +148,7 @@ def convert_gif(wall: Path) -> Path:
     return output_path
 
 
-def set_wallpaper(wall: Path | str, no_smart: bool) -> None:
+def set_wallpaper(wall: Path, no_smart: bool) -> None:
     # Make path absolute
     wall = Path(wall).resolve()