diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index c3f5a729e..b96bbafd6 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -13,7 +13,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
-          python-version: '3.9'
+          python-version: '3.10'
       - uses: pre-commit/action@v3.0.1
 
   tests-core:
@@ -23,12 +23,12 @@ jobs:
       fail-fast: false # Set on "false" to get the results of ALL builds
       matrix:
         os: ["ubuntu-latest"]
-        python-version: ["3.9", "3.12", "3.13"]
+        python-version: ["3.10", "3.12", "3.13"]
         sphinx-version: ["7.4", "8.2"]
         include:
           # corner cases for Windows
           - os: "windows-latest"
-            python-version: "3.9"
+            python-version: "3.10"
             sphinx-version: "7.4"
           - os: "windows-latest"
             python-version: "3.12"
@@ -39,7 +39,7 @@ jobs:
         exclude:
           # Sphinx 8.2 only supports py3.11+
           - os: "ubuntu-latest"
-            python-version: "3.9"
+            python-version: "3.10"
             sphinx-version: "8.2"
 
     steps:
@@ -81,7 +81,7 @@ jobs:
       matrix:
         include:
           - os: "ubuntu-latest"
-            python-version: "3.9"
+            python-version: "3.10"
             sphinx-version: "7.4"
           - os: "ubuntu-latest"
             python-version: "3.13"
diff --git a/docs/contributing.rst b/docs/contributing.rst
index 25420f7e2..b500bf35d 100644
--- a/docs/contributing.rst
+++ b/docs/contributing.rst
@@ -85,7 +85,7 @@ Or use tox (recommended):
 
 .. code-block:: bash
 
-   tox -e py39
+   tox -e py310
 
 Note some tests use `syrupy <https://github.com/tophat/syrupy>`__ to perform snapshot testing.
 These snapshots can be updated by running:
diff --git a/pyproject.toml b/pyproject.toml
index c9f4635b7..32eecab91 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -17,7 +17,6 @@ classifiers = [
   'Operating System :: OS Independent',
   'Programming Language :: Python',
   'Programming Language :: Python :: 3',
-  'Programming Language :: Python :: 3.9',
   'Programming Language :: Python :: 3.10',
   'Programming Language :: Python :: 3.11',
   'Programming Language :: Python :: 3.12',
@@ -26,7 +25,7 @@ classifiers = [
   'Topic :: Utilities',
   'Framework :: Sphinx :: Extension',
 ]
-requires-python = ">=3.9,<4"
+requires-python = ">=3.10,<4"
 dependencies = [
   "sphinx>=7.4,<9",
   "requests-file~=2.1",             # external links
@@ -145,19 +144,19 @@ disable_error_code = ["no-redef"]
 
 legacy_tox_ini = """
 [tox]
-envlist = py39
+envlist = py10
 
 [testenv]
 usedevelop = true
 
-[testenv:py{39,310,311,312,313}]
+[testenv:py{310,311,312,313}]
 extras =
   test
   test-parallel
 commands =
   pytest --ignore tests/benchmarks {posargs:tests}
 
-[testenv:py{39,310,311,312,313}-benchmark]
+[testenv:py{310,311,312,313}-benchmark]
 extras =
   test
   benchmark
diff --git a/sphinx_needs/api/configuration.py b/sphinx_needs/api/configuration.py
index d4a2bb86c..090d1109f 100644
--- a/sphinx_needs/api/configuration.py
+++ b/sphinx_needs/api/configuration.py
@@ -6,7 +6,7 @@
 
 from __future__ import annotations
 
-from typing import Callable
+from collections.abc import Callable
 
 from sphinx.application import Sphinx
 from sphinx.util.logging import SphinxLoggerAdapter
diff --git a/sphinx_needs/config.py b/sphinx_needs/config.py
index 7caa8420e..3c245609c 100644
--- a/sphinx_needs/config.py
+++ b/sphinx_needs/config.py
@@ -1,8 +1,8 @@
 from __future__ import annotations
 
-from collections.abc import Mapping
+from collections.abc import Callable, Mapping
 from dataclasses import MISSING, dataclass, field, fields
-from typing import TYPE_CHECKING, Any, Callable, Literal, TypedDict
+from typing import TYPE_CHECKING, Any, Literal, TypedDict
 
 from docutils.parsers.rst import directives
 from sphinx.application import Sphinx
diff --git a/sphinx_needs/debug.py b/sphinx_needs/debug.py
index 8c847a15d..975d0e02d 100644
--- a/sphinx_needs/debug.py
+++ b/sphinx_needs/debug.py
@@ -8,11 +8,12 @@
 import inspect
 import json
 import os.path
+from collections.abc import Callable
 from datetime import datetime
 from functools import wraps
 from pathlib import Path
 from timeit import default_timer as timer  # Used for timing measurements
-from typing import Any, Callable, TypeVar
+from typing import Any, TypeVar
 
 from jinja2 import Environment, PackageLoader, select_autoescape
 from sphinx.application import Sphinx
diff --git a/sphinx_needs/directives/need.py b/sphinx_needs/directives/need.py
index ac84d06d4..88c814990 100644
--- a/sphinx_needs/directives/need.py
+++ b/sphinx_needs/directives/need.py
@@ -1,8 +1,8 @@
 from __future__ import annotations
 
 import re
-from collections.abc import Sequence
-from typing import Any, Callable
+from collections.abc import Callable, Sequence
+from typing import Any
 
 from docutils import nodes
 from sphinx.addnodes import desc_name, desc_signature
diff --git a/sphinx_needs/directives/needbar.py b/sphinx_needs/directives/needbar.py
index 833d1a03f..bb63ea5a5 100644
--- a/sphinx_needs/directives/needbar.py
+++ b/sphinx_needs/directives/needbar.py
@@ -390,7 +390,9 @@ def process_needbar(
 
             if current_needbar["stacked"]:
                 # handle stacked bar
-                y_offset = [i + j for i, j in zip(y_offset, local_data_number[x])]
+                y_offset = [
+                    i + j for i, j in zip(y_offset, local_data_number[x], strict=False)
+                ]
 
             if current_needbar["show_sum"]:
                 try:
@@ -427,7 +429,8 @@ def process_needbar(
                 matplotlib.pyplot.setp(bar_labels, rotation=int(sum_rotation))
 
         centers = [
-            (i + j) / 2.0 for i, j in zip(index[0], index[len(local_data_number) - 1])
+            (i + j) / 2.0
+            for i, j in zip(index[0], index[len(local_data_number) - 1], strict=False)
         ]
         if not current_needbar["horizontal"]:
             # We want to support even older version of matplotlib, which do not support axes.set_xticks(labels)
diff --git a/sphinx_needs/directives/needextend.py b/sphinx_needs/directives/needextend.py
index b4e88be27..c9fb100eb 100644
--- a/sphinx_needs/directives/needextend.py
+++ b/sphinx_needs/directives/needextend.py
@@ -1,7 +1,7 @@
 from __future__ import annotations
 
-from collections.abc import Sequence
-from typing import Any, Callable
+from collections.abc import Callable, Sequence
+from typing import Any
 
 from docutils import nodes
 from docutils.parsers.rst import directives
diff --git a/sphinx_needs/directives/needflow/_graphviz.py b/sphinx_needs/directives/needflow/_graphviz.py
index 83b658e2b..ed8d9a256 100644
--- a/sphinx_needs/directives/needflow/_graphviz.py
+++ b/sphinx_needs/directives/needflow/_graphviz.py
@@ -2,8 +2,9 @@
 
 import html
 import textwrap
+from collections.abc import Callable
 from functools import cache
-from typing import Callable, Literal, TypedDict
+from typing import Literal, TypedDict
 from urllib.parse import urlparse
 
 from docutils import nodes
diff --git a/sphinx_needs/directives/needservice.py b/sphinx_needs/directives/needservice.py
index 3126fc46e..42fc9bda8 100644
--- a/sphinx_needs/directives/needservice.py
+++ b/sphinx_needs/directives/needservice.py
@@ -1,7 +1,7 @@
 from __future__ import annotations
 
-from collections.abc import Sequence
-from typing import Any, Callable
+from collections.abc import Callable, Sequence
+from typing import Any
 
 from docutils import nodes
 from docutils.parsers.rst import directives
diff --git a/sphinx_needs/directives/needtable.py b/sphinx_needs/directives/needtable.py
index d006499fd..6583fdf14 100644
--- a/sphinx_needs/directives/needtable.py
+++ b/sphinx_needs/directives/needtable.py
@@ -1,8 +1,8 @@
 from __future__ import annotations
 
 import re
-from collections.abc import Sequence
-from typing import Any, Callable
+from collections.abc import Callable, Sequence
+from typing import Any
 
 from docutils import nodes
 from docutils.parsers.rst import directives
diff --git a/sphinx_needs/filter_common.py b/sphinx_needs/filter_common.py
index a01179611..ccc28703e 100644
--- a/sphinx_needs/filter_common.py
+++ b/sphinx_needs/filter_common.py
@@ -8,11 +8,11 @@
 import ast
 import json
 import re
-from collections.abc import Iterable
+from collections.abc import Callable, Iterable
 from pathlib import Path
 from timeit import default_timer as timer
 from types import CodeType
-from typing import Any, Callable, TypedDict, overload
+from typing import Any, TypedDict, overload
 
 from docutils import nodes
 from docutils.parsers.rst import directives
@@ -318,8 +318,8 @@ def _analyze_and_apply_expr(
     :returns: the needs (potentially filtered),
         and a boolean denoting if it still requires python eval filtering
     """
-    if isinstance(expr, (ast.Str, ast.Constant)):
-        if isinstance(expr.s, (str, bool)):
+    if isinstance(expr, ast.Str | ast.Constant):
+        if isinstance(expr.s, str | bool):
             # "value" / True / False
             return needs if expr.s else needs.filter_ids([]), False
 
@@ -335,13 +335,13 @@ def _analyze_and_apply_expr(
             if (
                 isinstance(expr.left, ast.Name)
                 and len(expr.comparators) == 1
-                and isinstance(expr.comparators[0], (ast.Str, ast.Constant))
+                and isinstance(expr.comparators[0], ast.Str | ast.Constant)
             ):
                 # x == "value"
                 field = expr.left.id
                 value = expr.comparators[0].s
             elif (
-                isinstance(expr.left, (ast.Str, ast.Constant))
+                isinstance(expr.left, ast.Str | ast.Constant)
                 and len(expr.comparators) == 1
                 and isinstance(expr.comparators[0], ast.Name)
             ):
@@ -369,9 +369,9 @@ def _analyze_and_apply_expr(
             if (
                 isinstance(expr.left, ast.Name)
                 and len(expr.comparators) == 1
-                and isinstance(expr.comparators[0], (ast.List, ast.Tuple, ast.Set))
+                and isinstance(expr.comparators[0], ast.List | ast.Tuple | ast.Set)
                 and all(
-                    isinstance(elt, (ast.Str, ast.Constant))
+                    isinstance(elt, ast.Str | ast.Constant)
                     for elt in expr.comparators[0].elts
                 )
             ):
@@ -386,7 +386,7 @@ def _analyze_and_apply_expr(
                     # type in ["a", "b", ...]
                     return needs.filter_types(values), False
             elif (
-                isinstance(expr.left, (ast.Str, ast.Constant))
+                isinstance(expr.left, ast.Str | ast.Constant)
                 and len(expr.comparators) == 1
                 and isinstance(expr.comparators[0], ast.Name)
                 and expr.comparators[0].id == "tags"
diff --git a/sphinx_needs/functions/functions.py b/sphinx_needs/functions/functions.py
index 525421f7b..f5af5b0a8 100644
--- a/sphinx_needs/functions/functions.py
+++ b/sphinx_needs/functions/functions.py
@@ -112,7 +112,9 @@ def execute_func(
         )
         return "??"
 
-    if func_return is not None and not isinstance(func_return, (str, int, float, list)):
+    if func_return is not None and not isinstance(
+        func_return, str | int | float | list
+    ):
         log_warning(
             logger,
             f"Return value of function {func_name!r} is of type {type(func_return)}. Allowed are str, int, float, list",
@@ -122,7 +124,7 @@ def execute_func(
         return "??"
     if isinstance(func_return, list):
         for i, element in enumerate(func_return):
-            if not isinstance(element, (str, int, float)):
+            if not isinstance(element, str | int | float):
                 log_warning(
                     logger,
                     f"Return value item {i} of function {func_name!r} is of type {type(element)}. Allowed are str, int, float",
@@ -204,7 +206,7 @@ def find_and_replace_node_content(
         return node
     else:
         for child in node.children:
-            if isinstance(child, (nodes.literal_block, nodes.literal, Need)):
+            if isinstance(child, nodes.literal_block | nodes.literal | Need):
                 # Do not parse literal blocks or nested needs
                 new_children.append(child)
                 continue
@@ -253,7 +255,7 @@ def resolve_dynamic_values(needs: NeedsMutable, app: Sphinx) -> None:
         for need_option in need:
             if need_option not in allowed_fields:
                 continue
-            if not isinstance(need[need_option], (list, set)):
+            if not isinstance(need[need_option], list | set):
                 func_call: str | None = "init"
                 while func_call:
                     try:
@@ -314,7 +316,7 @@ def resolve_dynamic_values(needs: NeedsMutable, app: Sphinx) -> None:
                         )
                     if func_call is None:
                         new_values.append(element)
-                    elif isinstance(func_return, (list, set)):
+                    elif isinstance(func_return, list | set):
                         new_values += func_return
                     else:
                         new_values += [func_return]
@@ -370,7 +372,7 @@ def resolve_variants_options(
         for var_option in variants_options:
             if (
                 var_option in need
-                and isinstance(need[var_option], (str, list, tuple, set))
+                and isinstance(need[var_option], str | list | tuple | set)
                 and (
                     result := match_variants(
                         need[var_option],
@@ -476,7 +478,7 @@ def _analyze_func_string(
     for arg in func_call.args:
         if isinstance(arg, ast.Num):
             func_args.append(arg.n)
-        elif isinstance(arg, (ast.Str, ast.BoolOp)):
+        elif isinstance(arg, ast.Str | ast.BoolOp):
             func_args.append(arg.s)  # type: ignore
         elif isinstance(arg, ast.List):
             arg_list: list[Any] = []
diff --git a/sphinx_needs/layout.py b/sphinx_needs/layout.py
index 1009ccad9..63e570aa9 100644
--- a/sphinx_needs/layout.py
+++ b/sphinx_needs/layout.py
@@ -9,11 +9,11 @@
 import os
 import re
 import uuid
+from collections.abc import Callable
 from contextlib import suppress
 from functools import lru_cache
 from optparse import Values
 from pathlib import Path
-from typing import Callable
 from urllib.parse import urlparse
 
 import requests
diff --git a/sphinx_needs/needs.py b/sphinx_needs/needs.py
index 863243fbb..7eab592c5 100644
--- a/sphinx_needs/needs.py
+++ b/sphinx_needs/needs.py
@@ -1,9 +1,10 @@
 from __future__ import annotations
 
 import contextlib
+from collections.abc import Callable
 from pathlib import Path
 from timeit import default_timer as timer  # Used for timing measurements
-from typing import Any, Callable, Literal
+from typing import Any, Literal
 
 from docutils import nodes
 from docutils.parsers.rst import directives
@@ -782,9 +783,9 @@ def _gather_field_defaults(
                 k: v for k, v in value.items() if k in {"predicates", "default"}
             }
             if "predicates" in single_default and (
-                not isinstance(single_default["predicates"], (list, tuple))
+                not isinstance(single_default["predicates"], list | tuple)
                 or not all(
-                    isinstance(x, (list, tuple))
+                    isinstance(x, list | tuple)
                     and len(x) == 2
                     and isinstance(x[0], str)
                     for x in single_default["predicates"]
@@ -798,9 +799,9 @@ def _gather_field_defaults(
                 )
                 continue
         elif (
-            isinstance(value, (list, tuple))
+            isinstance(value, list | tuple)
             and len(value) > 0
-            and all(isinstance(x, (list, tuple)) for x in value)
+            and all(isinstance(x, list | tuple) for x in value)
         ):
             old_format = True
             single_default = {"predicates": []}
@@ -830,7 +831,7 @@ def _gather_field_defaults(
                         "config",
                         None,
                     )
-        elif isinstance(value, (list, tuple)):
+        elif isinstance(value, list | tuple):
             old_format = True
             if len(value) == 2:
                 # single (value, predicate) pair
diff --git a/sphinx_needs/roles/need_ref.py b/sphinx_needs/roles/need_ref.py
index 118b1e317..3e3c26d70 100644
--- a/sphinx_needs/roles/need_ref.py
+++ b/sphinx_needs/roles/need_ref.py
@@ -50,7 +50,7 @@ def value_to_string(value: Any) -> str:
         return value
     elif isinstance(value, dict):
         return ";".join([str(i) for i in value.items()])
-    elif isinstance(value, (Iterable, list, tuple)):
+    elif isinstance(value, Iterable | list | tuple):
         return ";".join([str(i) for i in value])
 
     return str(value)
diff --git a/sphinx_needs/services/open_needs.py b/sphinx_needs/services/open_needs.py
index 7c312413e..23cc0b77c 100644
--- a/sphinx_needs/services/open_needs.py
+++ b/sphinx_needs/services/open_needs.py
@@ -142,7 +142,7 @@ def _extract_data(
         for item in data:
             extra_data = {}
             for name, selector in self.extra_data.items():
-                if not isinstance(selector, (tuple, list, str)):
+                if not isinstance(selector, tuple | list | str):
                     raise InvalidConfigException(
                         f"Given selector for {name} of extra_data must be a list or tuple. "
                         f'Got {type(selector)} with value "{selector}"'
@@ -172,7 +172,7 @@ def _extract_data(
 
             need_values = {}
             for name, selector in self.mappings.items():
-                if not isinstance(selector, (tuple, list, str)):
+                if not isinstance(selector, tuple | list | str):
                     raise InvalidConfigException(
                         f"Given selector for {name} of mapping must be a list or tuple. "
                         f'Got {type(selector)} with value "{selector}"'
@@ -186,7 +186,7 @@ def _extract_data(
                     need_values[name] = selector
                 else:
                     value = dict_get(item, selector)
-                    if isinstance(value, (tuple, list)):
+                    if isinstance(value, tuple | list):
                         if name == "links":
                             # Add a prefix to the referenced link if it is an ID of a need object in
                             # the data retrieved from the Open Needs Server or don't add prefix
diff --git a/sphinx_needs/utils.py b/sphinx_needs/utils.py
index ce577744e..2934118f4 100644
--- a/sphinx_needs/utils.py
+++ b/sphinx_needs/utils.py
@@ -5,9 +5,10 @@
 import operator
 import os
 import re
+from collections.abc import Callable
 from dataclasses import dataclass
 from functools import lru_cache, reduce, wraps
-from typing import TYPE_CHECKING, Any, Callable, Protocol, TypeVar
+from typing import TYPE_CHECKING, Any, Protocol, TypeVar
 from urllib.parse import urlparse
 
 from docutils import nodes
@@ -98,7 +99,7 @@ def row_col_maker(
 
     if need_key in need_info and need_info[need_key] is not None:  # type: ignore[literal-required]
         value = need_info[need_key]  # type: ignore[literal-required]
-        if isinstance(value, (list, set)):
+        if isinstance(value, list | set):
             data = value
         elif isinstance(value, str) and need_key in needs_string_links_option:
             data = re.split(r",|;", value)
@@ -530,7 +531,7 @@ def match_variants(
             for i in options_list
             if i not in (None, ";", "", " ")
         ]
-    elif isinstance(options, (list, set, tuple)):
+    elif isinstance(options, list | set | tuple):
         options_list = [str(opt) for opt in options]
     else:
         raise TypeError(
diff --git a/sphinx_needs/views.py b/sphinx_needs/views.py
index 43ab0d08b..31059a6c7 100644
--- a/sphinx_needs/views.py
+++ b/sphinx_needs/views.py
@@ -2,13 +2,13 @@
 
 from collections.abc import Iterable, Iterator, Mapping
 from itertools import chain
-from typing import TYPE_CHECKING, Optional
+from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
     from sphinx_needs.data import NeedsInfoType
 
 
-_IdSet = list[tuple[str, Optional[str]]]
+_IdSet = list[tuple[str, str | None]]
 """Set of (need, part) ids."""