diff --git a/.github/workflows/main.yaml b/.github/workflows/main.yaml
new file mode 100644
index 0000000..9c82d22
--- /dev/null
+++ b/.github/workflows/main.yaml
@@ -0,0 +1,75 @@
+name: CI
+on:
+  push:
+    branches:
+      - master
+    tags:
+      - '*'
+  pull_request:
+    branches:
+      - master
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest,windows-latest,macos-latest,macos-14]
+    steps:
+    - name: Retrieve the source code
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+    - name: Remove old MEX files
+      shell: bash
+      run: rm Solver/Mexfun/*.mex*
+    - name: Install MATLAB
+      uses: matlab-actions/setup-matlab@v2
+      with:
+        release: ${{ matrix.os == 'macos-14' && 'R2023b' || ( matrix.os == 'windows-latest' && 'R2021b' || 'R2021a' ) }}
+    - name: Build MEX files
+      uses: matlab-actions/run-command@v2
+      with:
+        command: install_sdpt3 -rebuild
+    - uses: actions/upload-artifact@v4
+      with:
+        name: mexfiles-${{ matrix.os }}
+        path: |
+          Solver/Mexfun/*.mex*
+  package:
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+    - name: Retrieve the source code
+      uses: actions/checkout@v3
+      with:
+        fetch-depth: 0
+    - uses: actions/download-artifact@v4
+      with:
+        name: mexfiles-ubuntu-latest
+    - uses: actions/download-artifact@v4
+      with:
+        name: mexfiles-windows-latest
+    - uses: actions/download-artifact@v4
+      with:
+        name: mexfiles-macos-latest
+    - uses: actions/download-artifact@v4
+      with:
+        name: mexfiles-macos-14
+    - name: Show files, build archives
+      run: |
+        mv *.mex* Solver/Mexfun/
+        mkdir ../archives
+        zip -r ../archives/sdpt3.zip . -x '.git/*' -x '.github/*'
+        tar cfz ../archives/sdpt3.tgz --exclude "./.git" --exclude "./.github" .
+        echo "--------"
+        tar tfz ../archives/sdpt3.tgz
+        echo "--------"
+        zipinfo ../archives/sdpt3.zip
+        echo "--------"
+    - uses: softprops/action-gh-release@v2
+      if: startsWith(github.ref, 'refs/tags/')
+      with:
+        files: |
+          ../archives/sdpt3.tgz
+          ../archives/sdpt3.zip
diff --git a/install_sdpt3.m b/install_sdpt3.m
index 9412494..796ad2e 100644
--- a/install_sdpt3.m
+++ b/install_sdpt3.m
@@ -23,6 +23,7 @@ function install_sdpt3( varargin )
 VERSION = [1,0.01]*sscanf(version,'%d.%d');
 if ISOCTAVE, prog = 'Octave'; else prog = 'Matlab'; end
 COMPUTER = computer;
+IS64BIT = strcmp(COMPUTER(end-1:end), '64');
 mext = mexext;
 
 %