diff --git a/doc/internals/contributing.rst b/doc/internals/contributing.rst
index 83b23fb388..90d7600866 100644
--- a/doc/internals/contributing.rst
+++ b/doc/internals/contributing.rst
@@ -205,7 +205,7 @@ You can also test by installing dependencies in your local environment:
 
   .. code-block:: shell
 
-     pip install .[test]
+     pip install . --group test
 
 To run JavaScript tests, use :program:`npm`:
 
diff --git a/doc/usage/installation.rst b/doc/usage/installation.rst
index 8b0aca1cab..27adf3ab67 100644
--- a/doc/usage/installation.rst
+++ b/doc/usage/installation.rst
@@ -56,7 +56,7 @@ Run the following command::
    Or, if writing documentation for a Python package,
    place the dependencies in the `pyproject.toml file`__::
 
-      $ pip install .[docs]
+      $ pip install . --group docs
 
    __ https://pip.pypa.io/en/stable/reference/requirements-file-format/
    __ https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#dependencies-optional-dependencies
diff --git a/pyproject.toml b/pyproject.toml
index 7174e56225..ef6b680485 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -88,35 +88,6 @@ dependencies = [
 ]
 dynamic = ["version"]
 
-[project.optional-dependencies]
-docs = [
-    "sphinxcontrib-websupport",
-]
-lint = [
-    "ruff==0.12.7",
-    "mypy==1.17.1",
-    "sphinx-lint>=0.9",
-    "types-colorama==0.4.15.20250801",
-    "types-defusedxml==0.7.0.20250708",
-    "types-docutils==0.21.0.20250525",
-    "types-Pillow==10.2.0.20240822",
-    "types-Pygments==2.19.0.20250715",
-    "types-requests==2.32.4.20250611",  # align with requests
-    "types-urllib3==1.26.25.14",
-    "pyright==1.1.400",
-    "pytest>=8.0",
-    "pypi-attestations==0.0.27",
-    "betterproto==2.0.0b6",
-]
-test = [
-    "pytest>=8.0",
-    "pytest-xdist[psutil]>=3.4",
-    "defusedxml>=0.7.1", # for secure XML/HTML parsing
-    "cython>=3.0",
-    "setuptools>=70.0",  # for Cython compilation
-    "typing_extensions>=4.9",  # for typing_extensions.Unpack
-]
-
 [[project.authors]]
 name = "Adam Turner"
 email = "aa-turner@users.noreply.github.com"