diff --git a/docs/generate_input_reference.py b/docs/generate_input_reference.py
index 95f50c9bee..80cf3a955c 100755
--- a/docs/generate_input_reference.py
+++ b/docs/generate_input_reference.py
@@ -28,7 +28,7 @@ def main() -> None:
 # ======================================================================================
 def build_bibliography(references_html_fn: str, output_dir: Path) -> None:
     content = Path(references_html_fn).read_text()
-    entries = re.findall("<TR>.*?</TR>", content, re.DOTALL)
+    entries = re.findall(r"<TR>.*?</TR>", content, re.DOTALL)
 
     output = []
     output += ["%", "% This file was created by generate_input_reference.py", "%"]
@@ -36,22 +36,22 @@ def build_bibliography(references_html_fn: str, output_dir: Path) -> None:
 
     for entry in entries:
         pattern = (
-            '<TR><TD>\[(.*?)\]</TD><TD>\n <A NAME="reference_\d+">(.*?)</A><br>'
-            "(.*?)</TD></TR>"
+            r'<TR><TD>\[(.*?)\]</TD><TD>\n <A NAME="reference_\d+">(.*?)</A><br>'
+            r"(.*?)</TD></TR>"
         )
         parts = re.search(pattern, entry, re.DOTALL)
         assert parts
         key = parts.group(1)
         title = parts.group(3).strip()
         if "<br>" in parts.group(2):
-            m = re.match("(.*?)<br>(.*)", parts.group(2), re.DOTALL)
+            m = re.match(r"(.*?)<br>(.*)", parts.group(2), re.DOTALL)
             assert m
             authors, mix = m.groups()
         else:
             authors, mix = "", parts.group(2)
 
         if "https://doi.org" in mix:
-            m = re.match('\s*<A HREF="(.*?)">(.*?)</A>', mix, re.DOTALL)
+            m = re.match(r'\s*<A HREF="(.*?)">(.*?)</A>', mix, re.DOTALL)
             assert m
             doi, ref = m.groups()
         else:
@@ -367,13 +367,13 @@ def sanitize_name(name: str) -> str:
 # ======================================================================================
 def escape_markdown(text: str) -> str:
     # Code blocks without a language get mistaken for the end of the py:data directive.
-    text = text.replace("\n\n```\n", "\n\n```none\n")
+    text = text.replace(r"\n\n```\n", r"\n\n```none\n")
 
     # Underscores are very common in our docs. Luckily asterisks also work for emphasis.
-    text = text.replace("__", "\_\_")
+    text = text.replace(r"__", r"\_\_")
 
     # Headings mess up the page structure. Please use paragraphs and bold text instead.
-    text = text.replace("#", "\#")
+    text = text.replace(r"#", r"\#")
 
     return text
 
diff --git a/tools/docker/generate_dockerfiles.py b/tools/docker/generate_dockerfiles.py
index 022ed10de2..a188b670aa 100755
--- a/tools/docker/generate_dockerfiles.py
+++ b/tools/docker/generate_dockerfiles.py
@@ -371,8 +371,8 @@ def install_cp2k(
     if revision:
         input_lines.append("ARG GIT_COMMIT_SHA")
         run_lines.append(
-            'if [ -n "${GIT_COMMIT_SHA}" ] ; then'
-            ' echo "git:\${GIT_COMMIT_SHA::7}" > REVISION; fi'
+            r'if [ -n "${GIT_COMMIT_SHA}" ] ; then'
+            r' echo "git:\${GIT_COMMIT_SHA::7}" > REVISION; fi'
         )
 
     input_lines.append("COPY ./Makefile .")
diff --git a/tools/precommit/check_file_properties.py b/tools/precommit/check_file_properties.py
index 55108141a5..24a0f488ca 100755
--- a/tools/precommit/check_file_properties.py
+++ b/tools/precommit/check_file_properties.py
@@ -7,7 +7,7 @@ import os
 import pathlib
 import re
 import sys
-from datetime import datetime
+from datetime import datetime, timezone
 from functools import lru_cache
 import itertools
 from typing import Tuple, List, TypeVar
@@ -77,7 +77,7 @@ FLAG_EXCEPTIONS = (
 FLAG_EXCEPTIONS_RE = re.compile(r"|".join(FLAG_EXCEPTIONS))
 PORTABLE_FILENAME_RE = re.compile(r"^[a-zA-Z0-9._/#~=+-]*$")
 OP_RE = re.compile(r"[\\|()!&><=*/+-]")
-NUM_RE = re.compile("[0-9]+[ulUL]*")
+NUM_RE = re.compile(r"[0-9]+[ulUL]*")
 CP2K_FLAGS_RE = re.compile(
     r"FUNCTION cp2k_flags\(\)(.*)END FUNCTION cp2k_flags", re.DOTALL
 )
@@ -183,7 +183,7 @@ def check_file(path: pathlib.Path) -> List[str]:
                 warnings += [f"{path}:{i+1} Double space in multi-line string"]
 
     # check banner
-    year = datetime.utcnow().year
+    year = datetime.now(timezone.utc).year
     bsd_licensed = any(str(path).startswith(d) for d in BSD_DIRECTORIES)
     spdx = "BSD-3-Clause    " if bsd_licensed else "GPL-2.0-or-later"
     if fn_ext == ".F" and not content.startswith(BANNER_F.format(year, spdx)):