diff --git a/scripts/benchmark.py b/scripts/benchmark.py
index 5483dac1..fe820d9b 100755
--- a/scripts/benchmark.py
+++ b/scripts/benchmark.py
@@ -11,7 +11,7 @@ import termios
 from datetime import datetime
 
 
-def main():
+def main() -> None:
     parser = argparse.ArgumentParser()
     parser.add_argument('files', type=argparse.FileType('rb'), nargs='+')
     parser.add_argument('--iterations', type=int, default=20)
@@ -24,12 +24,12 @@ def main():
                     termios.TIOCGWINSZ,
                     struct.pack('HHHH', 0, 0, 0, 0)))
 
-    times = {name: [] for name in [f.name for f in args.files]}
+    times: dict[str, list[float]] = {name: [] for name in [f.name for f in args.files]}
 
     for f in args.files:
         bench_bytes = f.read()
 
-        for i in range(args.iterations):
+        for _ in range(args.iterations):
             start = datetime.now()
             sys.stdout.buffer.write(bench_bytes)
             stop = datetime.now()
@@ -48,4 +48,4 @@ def main():
 
 
 if __name__ == '__main__':
-    sys.exit(main())
+    main()
diff --git a/scripts/generate-alt-random-writes.py b/scripts/generate-alt-random-writes.py
index 656a2b9d..7ad1460c 100755
--- a/scripts/generate-alt-random-writes.py
+++ b/scripts/generate-alt-random-writes.py
@@ -8,6 +8,8 @@ import struct
 import sys
 import termios
 
+from typing import Any
+
 
 class ColorVariant(enum.IntEnum):
     NONE = enum.auto()
@@ -17,7 +19,7 @@ class ColorVariant(enum.IntEnum):
     RGB = enum.auto()
 
 
-def main():
+def main() -> None:
     parser = argparse.ArgumentParser()
     parser.add_argument(
         'out', type=argparse.FileType(mode='w'), nargs='?', help='name of output file')
@@ -38,10 +40,16 @@ def main():
     opts = parser.parse_args()
     out = opts.out if opts.out is not None else sys.stdout
 
+    lines: int | None = None
+    cols: int | None = None
+    width: int | None = None
+    height: int | None = None
+
     if opts.rows is None or opts.cols is None:
         try:
-            def dummy(*args):
+            def dummy(*args: Any) -> None:
                 """Need a handler installed for sigwait() to trigger."""
+                _ = args
                 pass
             signal.signal(signal.SIGWINCH, dummy)
 
@@ -53,6 +61,9 @@ def main():
                                     termios.TIOCGWINSZ,
                                     struct.pack('HHHH', 0, 0, 0, 0)))
 
+                assert width is not None
+                assert height is not None
+
                 if width > 0 and height > 0:
                     break
 
@@ -71,9 +82,11 @@ def main():
 
     if opts.rows is not None:
         lines = opts.rows
+        assert lines is not None
         height = 15 * lines  # PGO helper binary hardcodes cell height to 15px
     if opts.cols is not None:
         cols = opts.cols
+        assert cols is not None
         width = 8 * cols     # PGO help binary hardcodes cell width to 8px
 
     if lines is None or cols is None or height is None or width is None:
@@ -190,8 +203,8 @@ def main():
         # The sixel 'alphabet'
         sixels = '?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~'
 
-        last_pos = None
-        last_size = None
+        last_pos: tuple[int, int] | None = None
+        last_size: tuple[int, int] = 0, 0
 
         for _ in range(20):
             if last_pos is not None and random.randrange(2):
@@ -254,4 +267,4 @@ def main():
 
 
 if __name__ == '__main__':
-    sys.exit(main())
+    main()
diff --git a/scripts/generate-builtin-terminfo.py b/scripts/generate-builtin-terminfo.py
index 6a6ba68c..515153a2 100755
--- a/scripts/generate-builtin-terminfo.py
+++ b/scripts/generate-builtin-terminfo.py
@@ -3,13 +3,10 @@
 import argparse
 import os
 import re
-import sys
-
-from typing import Dict, Union
 
 
 class Capability:
-    def __init__(self, name: str, value: Union[bool, int, str]):
+    def __init__(self, name: str, value: bool | int | str) -> None:
         self._name = name
         self._value = value
 
@@ -18,30 +15,42 @@ class Capability:
         return self._name
 
     @property
-    def value(self) -> Union[bool, int, str]:
+    def value(self) -> bool | int | str:
         return self._value
 
-    def __lt__(self, other):
+    def __lt__(self, other: object) -> bool:
+        if not isinstance(other, Capability):
+            return NotImplemented
         return self._name < other._name
 
-    def __le__(self, other):
+    def __le__(self, other: object) -> bool:
+        if not isinstance(other, Capability):
+            return NotImplemented
         return self._name <= other._name
 
-    def __eq__(self, other):
+    def __eq__(self, other: object) -> bool:
+        if not isinstance(other, Capability):
+            return NotImplemented
         return self._name == other._name
 
-    def __ne__(self, other):
-        return self._name != other._name
+    def __ne__(self, other: object) -> bool:
+        if not isinstance(other, Capability):
+            return NotImplemented
+        return bool(self._name != other._name)
 
-    def __gt__(self, other):
-        return self._name > other._name
+    def __gt__(self, other: object) -> bool:
+        if not isinstance(other, Capability):
+            return NotImplemented
+        return bool(self._name > other._name)
 
-    def __ge__(self, other):
+    def __ge__(self, other: object) -> bool:
+        if not isinstance(other, Capability):
+            return NotImplemented
         return self._name >= other._name
 
 
 class BoolCapability(Capability):
-    def __init__(self, name: str):
+    def __init__(self, name: str) -> None:
         super().__init__(name, True)
 
 
@@ -50,11 +59,11 @@ class IntCapability(Capability):
 
 
 class StringCapability(Capability):
-    def __init__(self, name: str, value: str):
+    def __init__(self, name: str, value: str) -> None:
         # see terminfo(5) for valid escape sequences
 
         # Control characters
-        def translate_ctrl_chr(m):
+        def translate_ctrl_chr(m: re.Match[str]) -> str:
             ctrl = m.group(1)
             if ctrl == '?':
                 return '\\x7f'
@@ -83,10 +92,10 @@ class StringCapability(Capability):
 
 
 class Fragment:
-    def __init__(self, name: str, description: str):
+    def __init__(self, name: str, description: str) -> None:
         self._name = name
         self._description = description
-        self._caps = {}
+        self._caps = dict[str, Capability]()
 
     @property
     def name(self) -> str:
@@ -97,18 +106,18 @@ class Fragment:
         return self._description
 
     @property
-    def caps(self) -> Dict[str, Capability]:
+    def caps(self) -> dict[str, Capability]:
         return self._caps
 
-    def add_capability(self, cap: Capability):
+    def add_capability(self, cap: Capability) -> None:
         assert cap.name not in self._caps
         self._caps[cap.name] = cap
 
-    def del_capability(self, name: str):
+    def del_capability(self, name: str) -> None:
         del self._caps[name]
 
 
-def main():
+def main() -> None:
     parser = argparse.ArgumentParser()
     parser.add_argument('source_entry_name')
     parser.add_argument('source', type=argparse.FileType('r'))
@@ -121,15 +130,15 @@ def main():
     source = opts.source
     target = opts.target
 
-    lines = []
-    for l in source.readlines():
-        l = l.strip()
-        if l.startswith('#'):
+    lines = list[str]()
+    for line in source.readlines():
+        line = line.strip()
+        if line.startswith('#'):
             continue
-        lines.append(l)
+        lines.append(line)
 
-    fragments = {}
-    cur_fragment = None
+    fragments = dict[str, Fragment]()
+    cur_fragment: Fragment | None = None
 
     for m in re.finditer(
             r'(?P<name>(?P<entry_name>[-+\w@]+)\|(?P<entry_desc>.+?),)|'
@@ -148,17 +157,20 @@ def main():
 
         elif m.group('bool_cap') is not None:
             name = m.group('bool_name')
+            assert cur_fragment is not None
             cur_fragment.add_capability(BoolCapability(name))
 
         elif m.group('int_cap') is not None:
             name = m.group('int_name')
-            value = int(m.group('int_val'), 0)
-            cur_fragment.add_capability(IntCapability(name, value))
+            int_value = int(m.group('int_val'), 0)
+            assert cur_fragment is not None
+            cur_fragment.add_capability(IntCapability(name, int_value))
 
         elif m.group('str_cap') is not None:
             name = m.group('str_name')
-            value = m.group('str_val')
-            cur_fragment.add_capability(StringCapability(name, value))
+            str_value = m.group('str_val')
+            assert cur_fragment is not None
+            cur_fragment.add_capability(StringCapability(name, str_value))
 
         else:
             assert False
@@ -167,6 +179,9 @@ def main():
     for frag in fragments.values():
         for cap in frag.caps.values():
             if cap.name == 'use':
+                assert isinstance(cap, StringCapability)
+                assert isinstance(cap.value, str)
+
                 use_frag = fragments[cap.value]
                 for use_cap in use_frag.caps.values():
                     frag.add_capability(use_cap)
@@ -188,7 +203,7 @@ def main():
     entry.add_capability(IntCapability('RGB', 8))  # 8 bits per channel
     entry.add_capability(StringCapability('query-os-name', os.uname().sysname))
 
-    terminfo_parts = []
+    terminfo_parts = list[str]()
     for cap in sorted(entry.caps.values()):
         name = cap.name
         value = str(cap.value)
@@ -212,4 +227,4 @@ def main():
 
 
 if __name__ == '__main__':
-    sys.exit(main())
+    main()
diff --git a/scripts/generate-emoji-variation-sequences.py b/scripts/generate-emoji-variation-sequences.py
index e05b6290..17172d20 100644
--- a/scripts/generate-emoji-variation-sequences.py
+++ b/scripts/generate-emoji-variation-sequences.py
@@ -1,11 +1,10 @@
 #!/usr/bin/env python3
 
 import argparse
-import sys
 
 
 class Codepoint:
-    def __init__(self, start: int, end: None|int = None):
+    def __init__(self, start: int, end: None | int = None) -> None:
         self.start = start
         self.end = start if end is None else end
         self.vs15 = False
@@ -15,7 +14,7 @@ class Codepoint:
         return f'{self.start:x}-{self.end:x}, vs15={self.vs15}, vs16={self.vs16}'
 
 
-def main():
+def main() -> None:
     parser = argparse.ArgumentParser()
     parser.add_argument('input', type=argparse.FileType('r'))
     parser.add_argument('output', type=argparse.FileType('w'))
@@ -100,4 +99,4 @@ def main():
 
 
 if __name__ == '__main__':
-    sys.exit(main())
+    main()
diff --git a/scripts/srgb.py b/scripts/srgb.py
index 12056956..a6aa0f4a 100755
--- a/scripts/srgb.py
+++ b/scripts/srgb.py
@@ -2,7 +2,6 @@
 
 import argparse
 import math
-import sys
 
 
 # Note: we use a pure gamma 2.2 function, rather than the piece-wise
@@ -17,7 +16,7 @@ def linear_to_srgb(f: float) -> float:
     return math.pow(f, 1 / 2.2)
 
 
-def main():
+def main() -> None:
     parser = argparse.ArgumentParser()
     parser.add_argument('c_output', type=argparse.FileType('w'))
     parser.add_argument('h_output', type=argparse.FileType('w'))
@@ -68,4 +67,4 @@ def main():
 
 
 if __name__ == '__main__':
-    sys.exit(main())
+    main()