diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 7044a440..04a6cf56 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -12,13 +12,13 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/cache@v2
+      - uses: actions/checkout@v4
+      - uses: actions/cache@v4
         with:
           key: ${{ github.ref }}
           path: .cache
       - name: Set up python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: "3.10"
       - name: Upgrade pip
@@ -44,7 +44,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - {python-version: "3.9",  backend: "numpy",      os: ubuntu-latest, coverage: True,  minimal: True, full: True}
           - {python-version: "3.10", backend: "numpy",      os: ubuntu-latest, coverage: True,  minimal: True, full: True}
           - {python-version: "3.11", backend: "numpy",      os: ubuntu-latest, coverage: True,  minimal: True, full: True}
           - {python-version: "3.12", backend: "numpy",      os: ubuntu-latest, coverage: False, minimal: True, full: True}
@@ -52,13 +51,13 @@ jobs:
           - {python-version: "3.12", backend: "jax",        os: ubuntu-latest, coverage: False, minimal: True, full: False}
 
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/cache@v2
+      - uses: actions/checkout@v4
+      - uses: actions/cache@v4
         with:
           key: ${{ github.ref }}
           path: .cache
       - name: Set up python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
       - name: Upgrade pip
@@ -97,13 +96,13 @@ jobs:
     if: github.ref == 'refs/heads/master'
 
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/cache@v2
+      - uses: actions/checkout@v4
+      - uses: actions/cache@v4
         with:
           key: ${{ github.ref }}
           path: .cache
       - name: Set up python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: "3.10"
       - name: Upgrade pip
diff --git a/.github/workflows/publish.yaml b/.github/workflows/publish.yaml
index e298f296..f8a5e3cc 100644
--- a/.github/workflows/publish.yaml
+++ b/.github/workflows/publish.yaml
@@ -17,11 +17,11 @@ jobs:
       id-token: write
 
     steps:
-      - uses: actions/checkout@v2
-      - name: Set up python "3.9"
-        uses: actions/setup-python@v2
+      - uses: actions/checkout@v4
+      - name: Set up python "3.10"
+        uses: actions/setup-python@v4
         with:
-          python-version: "3.9"
+          python-version: "3.10"
       - name: Upgrade pip
         run: |
           python -m pip install --upgrade pip
diff --git a/ebcc/ext/fci.py b/ebcc/ext/fci.py
index 03194c39..62437c58 100644
--- a/ebcc/ext/fci.py
+++ b/ebcc/ext/fci.py
@@ -399,9 +399,11 @@ def _get_c(spins: str) -> NDArray[T]:
         cn = ci[addrsi, addrsj] * signsi * signsj
 
         # Decompress the axes
+        spins_full = spins + spins
+        spins_full = spins_full[::2] + spins_full[1::2]
         shape = tuple(
             space["ab".index(s)].size(char)
-            for char, s in zip("O" * nalph + "V" * nalph + "O" * nbeta + "V" * nbeta, spins + spins)
+            for char, s in zip("O" * nalph + "V" * nalph + "O" * nbeta + "V" * nbeta, spins_full)
         )
         subscript = "i" * nalph + "a" * nalph + "j" * nbeta + "b" * nbeta
         cn = util.decompress_axes(subscript, cn, shape=shape)
diff --git a/ebcc/util/einsumfunc.py b/ebcc/util/einsumfunc.py
index 6c71f205..352cfd1e 100644
--- a/ebcc/util/einsumfunc.py
+++ b/ebcc/util/einsumfunc.py
@@ -511,7 +511,7 @@ def einsum(
         # If it's a chain of contractions, use the path optimizer
         args = list(args)
         path_kwargs = dict(optimize=optimize, einsum_call=True)
-        contractions = np.einsum_path(subscript, *args, **path_kwargs)[1]
+        contractions = np.einsum_path(subscript, *args, **path_kwargs)[1]  # type: ignore[arg-type]
         for contraction in contractions:
             inds, idx_rm, einsum_str, remain = list(contraction[:4])
             contraction_args = [args.pop(x) for x in inds]  # type: ignore