diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..7bbb446
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,58 @@
+# Author: A Taylor | Purpose: Continuous integration for tri-language test suites
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  # ---------------------------------------------------------------------------
+  # Python test suite (pytest + astropy.units)
+  # ---------------------------------------------------------------------------
+  python:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ["3.10", "3.11", "3.12"]
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install dependencies
+        run: |
+          cd python
+          pip install -e ".[dev]"
+
+      - name: Run pytest
+        run: |
+          cd python
+          pytest tests/ -v --tb=short
+
+  # ---------------------------------------------------------------------------
+  # C++ test suite (CMake + GoogleTest)
+  # ---------------------------------------------------------------------------
+  cpp:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Configure CMake
+        run: |
+          cd cpp
+          cmake -B build -DCMAKE_BUILD_TYPE=Release
+
+      - name: Build
+        run: |
+          cd cpp
+          cmake --build build
+
+      - name: Run CTest
+        run: |
+          cd cpp/build
+          ctest --output-on-failure