diff --git a/.github/workflows/build_docs.yml b/.github/workflows/build_docs.yml
index d9c7e113..99b2fa12 100644
--- a/.github/workflows/build_docs.yml
+++ b/.github/workflows/build_docs.yml
@@ -13,7 +13,7 @@
      strategy:
        matrix:
          os: ['ubuntu-latest']
-         environment-file: [.ci/39.yml]
+         environment-file: [ci/312.yml]
          experimental: [false]
      defaults:
        run:
diff --git a/.github/workflows/unittests.yml b/.github/workflows/unittests.yml
index 139db760..9533a01a 100644
--- a/.github/workflows/unittests.yml
+++ b/.github/workflows/unittests.yml
@@ -2,70 +2,88 @@
 
  on:
    push:
-     branches: [main]
+     branches:
+     - '*'
    pull_request:
      branches:
      - '*'
    schedule:
-     - cron: "0 0 * * 1,4"
+     - cron: '59 23 * * *'
    workflow_dispatch:
-     inputs:
-       version:
-         description: Manual Unittest Run
-         default: test
-         required: false
+    inputs:
+      version:
+        description: Manual CI Run
+        default: test
+        required: false
 
  jobs:
-   Tests:
+   tests:
      name: ${{ matrix.os }}, ${{ matrix.environment-file }}
      runs-on: ${{ matrix.os }}
+     timeout-minutes: 30
      strategy:
-       fail-fast: false
        matrix:
          os: [ubuntu-latest]
-         environment-file:
-           - ci/310.yml
-           - ci/311.yml
-           - ci/312.yml
+         environment-file: [
+            ci/311.yml,
+            ci/312.yml,
+            ci/313.yml,
+         ]
          include:
            - environment-file: ci/312.yml
              os: macos-13 # Intel
            - environment-file: ci/312.yml
-             os: macos-14  # Apple Silicon
+             os: macos-14 # Apple Silicon
            - environment-file: ci/312.yml
              os: windows-latest
+       fail-fast: false
+
      defaults:
        run:
          shell: bash -l {0}
- 
+
      steps:
-       - uses: actions/checkout@v4
- 
+       - name: checkout repo
+         uses: actions/checkout@v4
+         with:
+           fetch-depth: 0 # Fetch all history for all branches and tags.
+
        - name: setup micromamba
          uses: mamba-org/setup-micromamba@v1
          with:
            environment-file: ${{ matrix.environment-file }}
            micromamba-version: 'latest'
- 
-       - name: Test segregation
+
+       - name: environment info
          run: |
-           pytest \
-           segregation \
+           micromamba info
+           micromamba list
+
+       - name: spatial versions
+         run: 'python -c "import geopandas; geopandas.show_versions();"'
+
+       - name: install package
+         run: 'pip install . --no-deps'
+
+       - name: run tests
+         run: |
+           pytest segregation \
            -v \
            -r a \
+           -n auto \
            --color yes \
            --cov segregation \
            --cov-append \
            --cov-report term-missing \
-           --cov-report xml \
+           --cov-report xml
 
        - name: codecov
-         uses: codecov/codecov-action@v4
+         uses: codecov/codecov-action@v3
          with:
            token: ${{ secrets.CODECOV_TOKEN }}
            file: ./coverage.xml
            name: segregation-codecov
- 
+
        - name: Generate and publish the report
          if: |
            failure()
diff --git a/ci/310.yml b/ci/313.yml
similarity index 95%
rename from ci/310.yml
rename to ci/313.yml
index 5bc24a64..2d2d5b36 100644
--- a/ci/310.yml
+++ b/ci/313.yml
@@ -2,7 +2,7 @@ name: test
 channels:
   - conda-forge
 dependencies:
-  - python=3.10
+  - python=3.13
   - deprecation
   - geopandas>=0.9
   - joblib
diff --git a/environment.yml b/environment.yml
index dfe61705..994d4b5e 100644
--- a/environment.yml
+++ b/environment.yml
@@ -3,7 +3,7 @@ channels:
   - conda-forge
   - defaults
 dependencies:
-  - python=3.9
+  - python>=3.12
   - deprecation
   - geopandas>=0.9
   - joblib
diff --git a/pyproject.toml b/pyproject.toml
index a30dd558..ef84bc77 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -27,7 +27,7 @@ classifiers = [
     "Intended Audience :: Science/Research",
     "Topic :: Scientific/Engineering :: GIS",
 ]
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 dependencies = [
 "deprecation",
 "geopandas>=0.9",
diff --git a/segregation/singlegroup/relative_centralization.py b/segregation/singlegroup/relative_centralization.py
index f082d8d2..7fbd8d47 100644
--- a/segregation/singlegroup/relative_centralization.py
+++ b/segregation/singlegroup/relative_centralization.py
@@ -145,8 +145,8 @@ def _relative_centralization(
     Xi = np.cumsum(x[asc_ind]) / X
     Yi = np.cumsum(y[asc_ind]) / Y
 
-    RCE = np.nansum(shift(Xi, 1, cval=np.NaN) * Yi) - np.nansum(
-        Xi * shift(Yi, 1, cval=np.NaN)
+    RCE = np.nansum(shift(Xi, 1, cval=np.nan) * Yi) - np.nansum(
+        Xi * shift(Yi, 1, cval=np.nan)
     )
 
     core_data = data[[group_pop_var, total_pop_var, data.geometry.name]]