diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 2244163..86e82de 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -28,12 +28,10 @@ jobs:
 
       - name: "Install test and project dependencies"
         run: |
-          # Project dependencies from pyproject.toml
+          # Project dependencies + test dependencies from pyproject.toml
           # NOTE: Also builds viscm. How do we avoid this?
-          pip install .
+          pip install --group dev . ${{ matrix.pyqt-dependency }}
 
-          # Test dependencies
-          pip install pytest pytest-cov pytest-qt pytest-xvfb ${{ matrix.pyqt-dependency }}
           # pytest-qt CI dependencies: https://pytest-qt.readthedocs.io/en/latest/troubleshooting.html#github-actions
           sudo apt update
           sudo apt install -y \
@@ -48,8 +46,5 @@ jobs:
           # variable`, unless this variable is set:
           MPLBACKEND: "Agg"
 
-      - name: "Install mypy"
-        run: "pip install mypy>=1.3"
-
       - name: "Run typechecker"
         run: "make typecheck"
diff --git a/pyproject.toml b/pyproject.toml
index f5cb284..b2ebbb7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -28,6 +28,15 @@ dependencies = [
 PySide = ["PySide6"]
 PyQt = ["PyQt6"]
 
+[dependency-groups]
+dev = [
+    "mypy>=1.19.1",
+    "pytest>=8.4.2",
+    "pytest-cov>=7.1.0",
+    "pytest-qt>=4.5.0",
+    "pytest-xvfb>=3.1.1",
+]
+
 [project.urls]
 repository = "https://github.com/matplotlib/viscm"
 # documentation = "https://viscm.readthedocs.io"