diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9a196725b..cad67c575 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -6,7 +6,7 @@ on:
     branches: [main]
 jobs:
   lint:
-    runs-on: 'ubuntu-latest'
+    runs-on: ubuntu-latest
     steps:
       - name: Check out code.
         uses: actions/checkout@v4
@@ -42,26 +42,46 @@ jobs:
     steps:
       - name: Check out code.
         uses: actions/checkout@v4
+      - name: Install poetry
+        run: pip install poetry
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          cache: 'poetry'
+          cache-dependency-path: "tests/pyproject.toml"
+          python-version-file: "tests/pyproject.toml"
+      - name: Install dependencies
+        run: |
+          cd tests || exit
+          poetry install --only dev
       - name: spell check
         run: |
-          pip install codespell==2.2
-          git grep --cached -l '' | grep -v -e 'History\.md' -e 'AUTHORS' -e 'man/.*\.1' -e 'man/.*\.html' | xargs codespell --ignore-words=.github/.ignore_words
+          cd tests
+          git grep --cached -l '' .. | \
+            grep -v -e 'History\.md' -e 'AUTHORS' -e 'man/.*\.1' -e 'man/.*\.html' | \
+            xargs poetry run codespell --ignore-words=../.github/.ignore_words
 
   test:
     runs-on: ubuntu-latest
 
     steps:
       - uses: actions/checkout@v4
-      - name: Set up Python 3.12
+      - name: Install poetry
+        run: pip install poetry
+      - name: Set up Python
         uses: actions/setup-python@v5
         with:
-          python-version: '3.12'
+          cache: 'poetry'
+          cache-dependency-path: "tests/pyproject.toml"
+          python-version-file: "tests/pyproject.toml"
       - name: Install dependencies
         run: |
-          python -m pip install --upgrade pip
-          pip install pytest==8.1.2 GitPython==3.1.43 testpath==0.6.0
+          cd tests || exit
+          poetry install --only test
       - name: Unit test
-        run: make test
+        run: |
+          cd tests
+          poetry run pytest
 
   build:
     strategy:
@@ -76,11 +96,9 @@ jobs:
         uses: actions/checkout@v4
       - name: Linux Install
         if: matrix.platform == 'ubuntu-latest'
-        run: |
-          sudo apt-get install -y bsdmainutils
+        run: sudo apt-get install -y bsdmainutils
       - name: Script
-        run: |
-          ./check_integrity.sh
+        run: ./check_integrity.sh
       - name: Brew release
         if: matrix.platform == 'macos-latest'
         run: |
diff --git a/tests/poetry.lock b/tests/poetry.lock
index 5fa5e29de..bb52a52d1 100644
--- a/tests/poetry.lock
+++ b/tests/poetry.lock
@@ -1,4 +1,19 @@
-# This file is automatically @generated by Poetry 1.8.2 and should not be changed by hand.
+# This file is automatically @generated by Poetry 1.8.4 and should not be changed by hand.
+
+[[package]]
+name = "codespell"
+version = "2.2.0"
+description = "Codespell"
+optional = false
+python-versions = ">=3.6"
+files = [
+    {file = "codespell-2.2.0-py3-none-any.whl", hash = "sha256:3cc3fcb484a8302683add19e7d11504c79c79b10d4ea0675409417a044b27374"},
+    {file = "codespell-2.2.0.tar.gz", hash = "sha256:3dce0cd1348d277f8d934d1d4dcbbf510f9ddfd1b9005e9b25fb983189962561"},
+]
+
+[package.extras]
+dev = ["check-manifest", "flake8", "pytest", "pytest-cov", "pytest-dependency"]
+hard-encoding-detection = ["chardet"]
 
 [[package]]
 name = "colorama"
@@ -56,13 +71,13 @@ files = [
 
 [[package]]
 name = "packaging"
-version = "24.0"
+version = "24.2"
 description = "Core utilities for Python packages"
 optional = false
-python-versions = ">=3.7"
+python-versions = ">=3.8"
 files = [
-    {file = "packaging-24.0-py3-none-any.whl", hash = "sha256:2ddfb553fdf02fb784c234c7ba6ccc288296ceabec964ad2eae3777778130bc5"},
-    {file = "packaging-24.0.tar.gz", hash = "sha256:eb82c5e3e56209074766e6885bb04b8c38a0c015d0a30036ebe7ece34c9989e9"},
+    {file = "packaging-24.2-py3-none-any.whl", hash = "sha256:09abb1bccd265c01f4a3aa3f7a7db064b36514d2cba19a2f694fe6150451a759"},
+    {file = "packaging-24.2.tar.gz", hash = "sha256:c228a6dc5e932d346bc5739379109d49e8853dd8223571c7c5b55260edc0b97f"},
 ]
 
 [[package]]
@@ -127,5 +142,5 @@ test = ["pytest"]
 
 [metadata]
 lock-version = "2.0"
-python-versions = "^3.11"
-content-hash = "e73f9840c5f034acbd9b1ebc082e7ce4600ac3235991e57cd825c261a5f2e14e"
+python-versions = "^3.12"
+content-hash = "e730a1e6e7fd2f51858e8c8cfa8b56d606eadd7a0a629ca8af078904721a5159"
diff --git a/tests/pyproject.toml b/tests/pyproject.toml
index 43266570e..f9d8792ed 100644
--- a/tests/pyproject.toml
+++ b/tests/pyproject.toml
@@ -8,11 +8,16 @@ license = "MIT"
 readme = "README.md"
 
 [tool.poetry.dependencies]
-python = "^3.11"
+python = "^3.12"
+
+[tool.poetry.group.test.dependencies]
 pytest = "8.1.2"
 gitpython = "3.1.43"
 testpath = "0.6.0"
 
+[tool.poetry.group.dev.dependencies]
+codespell = "2.2"
+
 [tool.pytest.ini_options]
 minversion = "7.4"
 addopts = "-ra -q"