diff --git a/.constraints/py3.8.txt b/.constraints/py3.8.txt
deleted file mode 100644
index 1499061..0000000
--- a/.constraints/py3.8.txt
+++ /dev/null
@@ -1,223 +0,0 @@
-# This file was autogenerated by uv via the following command:
-#    uv pip compile pyproject.toml -o .constraints/py3.8.txt --all-extras --no-annotate --python-version=3.8 --no-emit-package setuptools
-accessible-pygments==0.0.4
-alabaster==0.7.13
-annotated-types==0.7.0
-anyio==4.4.0
-argon2-cffi==23.1.0
-argon2-cffi-bindings==21.2.0
-arrow==1.3.0
-asttokens==2.4.1
-async-lru==2.0.4
-attrs==24.2.0
-babel==2.16.0
-backcall==0.2.0
-beautifulsoup4==4.12.3
-bleach==6.1.0
-cachetools==5.5.0
-cattrs==24.1.0
-certifi==2024.8.30
-cffi==1.17.1
-cfgv==3.4.0
-chardet==5.2.0
-charset-normalizer==3.3.2
-click==8.1.7
-colorama==0.4.6
-comm==0.2.2
-contourpy==1.1.1
-coverage==7.6.1
-cryptography==43.0.1
-cycler==0.12.1
-dataproperty==1.0.1
-debugpy==1.8.5
-decorator==5.1.1
-defusedxml==0.7.1
-deprecated==1.2.14
-distlib==0.3.8
-docstring-to-markdown==0.15
-docutils==0.17.1
-dominate==2.9.1
-exceptiongroup==1.2.2
-execnet==2.1.1
-executing==2.1.0
-fastjsonschema==2.20.0
-feynman==2.1.0
-filelock==3.16.0
-fonttools==4.53.1
-fqdn==1.5.1
-gitdb==4.0.11
-gitpython==3.1.43
-greenlet==3.1.0
-h11==0.14.0
-httpcore==1.0.5
-httpx==0.27.2
-identify==2.6.0
-idna==3.8
-imagesize==1.4.1
-importlib-metadata==8.4.0
-importlib-resources==6.4.5
-iniconfig==2.0.0
-ipykernel==6.29.5
-ipython==8.12.3
-ipywidgets==8.1.5
-isoduration==20.11.0
-jedi==0.19.1
-jinja2==3.1.4
-json5==0.9.25
-jsonpointer==3.0.0
-jsonschema==4.23.0
-jsonschema-specifications==2023.12.1
-jupyter==1.1.1
-jupyter-cache==0.6.1
-jupyter-client==8.6.2
-jupyter-console==6.6.3
-jupyter-core==5.7.2
-jupyter-events==0.10.0
-jupyter-lsp==2.2.5
-jupyter-server==2.14.2
-jupyter-server-mathjax==0.2.6
-jupyter-server-terminals==0.5.3
-jupyterlab==4.2.5
-jupyterlab-code-formatter==3.0.2
-jupyterlab-git==0.50.1
-jupyterlab-lsp==5.1.0
-jupyterlab-myst==2.4.2
-jupyterlab-pygments==0.3.0
-jupyterlab-server==2.27.3
-jupyterlab-widgets==3.0.13
-kiwisolver==1.4.7
-latexcodec==3.0.0
-livereload==2.7.0
-lsprotocol==2023.0.1
-markdown-it-py==2.2.0
-markupsafe==2.1.5
-matplotlib==3.7.5
-matplotlib-inline==0.1.7
-mbstrdecoder==1.1.3
-mdit-py-plugins==0.3.5
-mdurl==0.1.2
-mistune==3.0.2
-mpmath==1.3.0
-mypy==1.11.2
-mypy-extensions==1.0.0
-myst-nb==0.17.2
-myst-parser==0.18.1
-nbclient==0.6.8
-nbconvert==7.16.4
-nbdime==4.0.2
-nbformat==5.10.4
-nbmake==1.5.4
-nest-asyncio==1.6.0
-nodeenv==1.9.1
-notebook==7.2.2
-notebook-shim==0.2.4
-numpy==1.24.4
-overrides==7.7.0
-packaging==24.1
-pandocfilters==1.5.1
-parso==0.8.4
-pathvalidate==3.2.1
-pexpect==4.9.0
-pickleshare==0.7.5
-pillow==10.4.0
-pkgutil-resolve-name==1.3.10
-platformdirs==4.3.2
-pluggy==1.5.0
-pre-commit==3.5.0
-prometheus-client==0.20.0
-prompt-toolkit==3.0.47
-psutil==6.0.0
-ptyprocess==0.7.0
-pure-eval==0.2.3
-pybtex==0.24.0
-pybtex-docutils==1.0.3
-pycparser==2.22
-pydantic==2.9.1
-pydantic-core==2.23.3
-pydata-sphinx-theme==0.14.4
-pygithub==2.4.0
-pygments==2.18.0
-pyjwt==2.9.0
-pynacl==1.5.0
-pyparsing==3.1.4
-pyproject-api==1.7.1
-pytablewriter==1.2.0
-pytest==8.3.3
-pytest-cov==5.0.0
-pytest-xdist==3.6.1
-python-dateutil==2.9.0.post0
-python-gitlab==4.10.0
-python-json-logger==2.0.7
-python-lsp-jsonrpc==1.1.2
-python-lsp-ruff==2.2.2
-python-lsp-server==1.12.0
-pytoolconfig==1.3.1
-pytz==2024.1
-pyyaml==6.0.2
-pyzmq==26.2.0
-referencing==0.35.1
-requests==2.32.3
-requests-toolbelt==1.0.0
-rfc3339-validator==0.1.4
-rfc3986-validator==0.1.1
-rope==1.13.0
-rpds-py==0.20.0
-ruff==0.6.4
-send2trash==1.8.3
-six==1.16.0
-smmap==5.0.1
-sniffio==1.3.1
-snowballstemmer==2.2.0
-soupsieve==2.6
-sphinx==5.3.0
-sphinx-api-relink==0.0.9
-sphinx-autobuild==2021.3.14
-sphinx-book-theme==1.0.1
-sphinx-codeautolink==0.15.2
-sphinx-comments==0.0.3
-sphinx-copybutton==0.5.2
-sphinx-design==0.5.0
-sphinx-hep-pdgref==0.2.0
-sphinx-pybtex-etal-style==0.0.2
-sphinx-thebe==0.3.1
-sphinx-togglebutton==0.3.2
-sphinxcontrib-applehelp==1.0.4
-sphinxcontrib-bibtex==2.6.2
-sphinxcontrib-devhelp==1.0.2
-sphinxcontrib-htmlhelp==2.0.1
-sphinxcontrib-jsmath==1.0.1
-sphinxcontrib-qthelp==1.0.3
-sphinxcontrib-serializinghtml==1.1.5
-sqlalchemy==2.0.34
-stack-data==0.6.3
-sympy==1.13.2
-tabledata==1.3.3
-tabulate==0.9.0
-tcolorpy==0.1.6
-terminado==0.18.1
-tinycss2==1.3.0
-tomli==2.0.1
-tornado==6.4.1
-tox==4.18.1
-traitlets==5.14.3
-typepy==1.3.2
-types-docutils==0.21.0.20240907
-types-python-dateutil==2.9.0.20240906
-types-pyyaml==6.0.12.20240808
-types-setuptools==74.1.0.20240907
-typing-extensions==4.12.2
-ujson==5.10.0
-uri-template==1.3.0
-urllib3==2.2.2
-virtualenv==20.26.4
-wcwidth==0.2.13
-webcolors==24.8.0
-webencodings==0.5.1
-websocket-client==1.8.0
-wheel==0.44.0
-widgetsnbextension==4.0.13
-wrapt==1.16.0
-zipp==3.20.1
-
-# The following packages were excluded from the output:
-# setuptools
diff --git a/docs/conf.py b/docs/conf.py
index ed21893..525b665 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -32,6 +32,7 @@
 api_github_repo = f"{ORGANIZATION}/{REPO_NAME}"
 api_target_substitutions: dict[str, str | tuple[str, str]] = {
     "datetime": "datetime.datetime",
+    "Path": "pathlib.Path",
 }
 author = "Common Partial Wave Analysis"
 autodoc_default_options = {
@@ -126,10 +127,10 @@
 }
 linkcheck_anchors = False
 linkcheck_ignore = [
-    "http://127.0.0.1:8000",
     "http://cgl.soic.indiana.edu/jpac/References.html",
     "https://doi.org/10.1002/andp.19955070504",  # 403 for onlinelibrary.wiley.com
     "https://doi.org/10.1093/ptep/ptaa104",
+    "https://doi.org/10.1103",
     "https://doi.org/10.1155/2020/6674595",  # 403 hidawi.com
     "https://home.fnal.gov/~kutschke/Angdist/angdist.ps",
     "https://physique.cuso.ch",
diff --git a/pyproject.toml b/pyproject.toml
index 9ccb218..3c3d5f2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,7 +18,6 @@ classifiers = [
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python",
     "Topic :: Scientific/Engineering :: Physics",
@@ -48,7 +47,7 @@ keywords = [
 license = {file = "LICENSE"}
 maintainers = [{email = "compwa-admin@ep1.rub.de"}]
 name = "PWA-pages"
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 
 [project.optional-dependencies]
 dev = [
diff --git a/src/pwa_pages/project_inventory.py b/src/pwa_pages/project_inventory.py
index dc4cbce..bdd4b89 100644
--- a/src/pwa_pages/project_inventory.py
+++ b/src/pwa_pages/project_inventory.py
@@ -1,13 +1,13 @@
 """Helper tools for writing tables."""
 
+from __future__ import annotations
+
 import argparse
 import json
 import re
 import sys
-from datetime import datetime
 from functools import partial
-from pathlib import Path
-from typing import Callable, Dict, Iterable, List, Optional, Sequence, Union
+from typing import TYPE_CHECKING, Callable, Optional, Union
 
 import yaml
 from pydantic import BaseModel, model_validator
@@ -15,26 +15,31 @@
 
 from .repo import Repo, get_repo
 
+if TYPE_CHECKING:
+    from collections.abc import Iterable, Sequence
+    from datetime import datetime
+    from pathlib import Path
+
 if sys.version_info < (3, 11):
     from typing_extensions import Self
 else:
     from typing import Self
 
 
-def load_yaml(path: Union[Path, str]) -> dict:
+def load_yaml(path: Path | str) -> dict:
     with open(path) as stream:
         return yaml.load(stream, Loader=yaml.SafeLoader)
 
 
 def to_html_table(
-    inventory: "ProjectInventory",
-    selected_languages: List[str],
+    inventory: ProjectInventory,
+    selected_languages: list[str],
     *,
     fetch: bool = False,
     min_percentage: float = 2.5,
-    hide_columns: Optional[Iterable[str]] = None,
+    hide_columns: Iterable[str] | None = None,
 ) -> str:
-    header_to_formatters: Dict[str, Callable[[Project], str]] = {
+    header_to_formatters: dict[str, Callable[[Project], str]] = {
         "Project": _create_project_entry,
         "Collaboration": partial(_format_collaboration, inventory=inventory),
         "Since": _fetch_first_commit_year if fetch else lambda _: "",
@@ -85,15 +90,15 @@ class SubProject(BaseModel):
 class Project(BaseModel):
     name: str
     url: str
-    collaboration: Optional[Union[List[str], str]] = None
-    languages: List[str] = []
-    sub_projects: Optional[List[SubProject]] = None
+    collaboration: Optional[Union[list[str], str]] = None
+    languages: list[str] = []
+    sub_projects: Optional[list[SubProject]] = None
     since: int = 0
 
 
 class ProjectInventory(BaseModel):
-    projects: List[Project]
-    collaborations: Dict[str, str] = {}
+    projects: list[Project]
+    collaborations: dict[str, str] = {}
 
     @model_validator(mode="after")
     def _check_collaboration_exists(self) -> Self:
@@ -154,9 +159,7 @@ def __replace_language(language: str) -> str:
     return language
 
 
-def _fetch_languages(
-    project: Union[Project, SubProject], min_percentage: float
-) -> List[str]:
+def _fetch_languages(project: Project | SubProject, min_percentage: float) -> list[str]:
     repo = get_repo(project.url)
     if repo is None:
         return []
@@ -203,7 +206,7 @@ def _get_date(
 
 def _get_subproject_timestamps(
     project: Project, date_getter: Callable[[Repo], datetime]
-) -> List[datetime]:
+) -> list[datetime]:
     if project.sub_projects is None:
         return []
     timestamps = []
@@ -216,7 +219,7 @@ def _get_subproject_timestamps(
     return timestamps
 
 
-def _format_collaboration(project: Project, inventory: "ProjectInventory") -> str:
+def _format_collaboration(project: Project, inventory: ProjectInventory) -> str:
     collaborations = project.collaboration
     if collaborations is None:
         return ""
@@ -249,7 +252,7 @@ def _enumerate_html_links(list_of_entries: Sequence[str]) -> str:
     return "<li>" + html
 
 
-def export_json_schema(argv: Optional[Sequence[str]] = None) -> int:
+def export_json_schema(argv: Sequence[str] | None = None) -> int:
     parser = argparse.ArgumentParser(
         "Create a JSON validation schema for a software project inventory file\n"
     )