diff --git a/.github/workflows/run_unit_tests.yml b/.github/workflows/run_unit_tests.yml
index 91e9b8e6..dea7ffbf 100644
--- a/.github/workflows/run_unit_tests.yml
+++ b/.github/workflows/run_unit_tests.yml
@@ -34,7 +34,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip setuptools
-        pip install .[test]
+        pip install . --group test
         pip install ${{ matrix.dependencies }}
     - name: Lint with flake8
       run: |
diff --git a/docs/development.rst b/docs/development.rst
index c7ac7b7b..ccec5172 100644
--- a/docs/development.rst
+++ b/docs/development.rst
@@ -61,7 +61,7 @@ Install requirements:
 
 .. code-block:: none
 
-    pip install .[test]
+    pip install . --group test
 
 Run tests (including checks for PEP8 compliance):
 
@@ -79,7 +79,7 @@ Install requirements:
 
 .. code-block:: none
 
-    pip install .[docs]
+    pip install . --group docs
 
 Build documentation in *HTML* format:
 
diff --git a/pyproject.toml b/pyproject.toml
index 276f28dd..d161a276 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -47,6 +47,8 @@ libjpeg = [
     "pylibjpeg-openjpeg>=2.0.0",
     "pylibjpeg>=2.0",
 ]
+
+[dependency-groups]
 test = [
     "mypy==1.15.0",
     "pytest==8.3.5",