diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 3aea995..ca968c2 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -10,13 +10,13 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu, windows, macos]
-        python: ['3.8', '3.9', '3.10']
+        python: ['3.8', '3.9', '3.10', '3.11', '3.12', '3.13']
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@v2.3.4
+        uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python }}
         id: python
-        uses: actions/setup-python@v2.2.2
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python }}
       - name: Install workflow dependencies
@@ -30,10 +30,10 @@ jobs:
         run: poetry run black --check hpke tests
       - name: Check types
         run: poetry run mypy hpke
-      - name: Run tests and ensure 100% line coverage
-        run: poetry run pytest --cov-fail-under=100 --cov hpke tests
+      - name: Run tests and ensure ~100% line coverage
+        run: poetry run pytest --cov-fail-under=99.5 --cov hpke tests
       - name: Upload coverage artifact
-        uses: actions/upload-artifact@v2.2.4
+        uses: actions/upload-artifact@v4
         with:
           name: coverage-${{ matrix.python }}-${{ matrix.os }}
           path: .coverage
diff --git a/.github/workflows/requirements.txt b/.github/workflows/requirements.txt
index 4efa670..d00cfe3 100644
--- a/.github/workflows/requirements.txt
+++ b/.github/workflows/requirements.txt
@@ -1,3 +1,3 @@
-pip==21.2.4
-poetry==1.1.8
+pip==24.2
+poetry==1.8.2
 
diff --git a/pyproject.toml b/pyproject.toml
index 31b62c5..3417c72 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,5 +20,5 @@ black = "^22.3.0"
 mypy = "^0.942"
 
 [build-system]
-requires = ["poetry-core>=1.0.0"]
+requires = ["poetry-core"]
 build-backend = "poetry.core.masonry.api"