diff --git a/.github/actions/build_cmake/action.yml b/.github/actions/build_cmake/action.yml
new file mode 100644
index 0000000000..7eda89bacc
--- /dev/null
+++ b/.github/actions/build_cmake/action.yml
@@ -0,0 +1,103 @@
+name: Build cmake
+inputs:
+  opt_level:
+    description: 'The optimization level'
+    required: false
+    default: generic
+  gpu:
+    description: 'The GPU to use'
+    required: false
+    default: OFF
+  raft:
+    description: 'The raft to use'
+    required: false
+    default: OFF
+runs:
+  using: composite
+  steps:
+    - name: Setup miniconda
+      uses: conda-incubator/setup-miniconda@v3.0.3
+      with:
+        python-version: '3.11'
+        miniconda-version: latest
+    - name: Set up environment
+      shell: bash
+      run: |
+        conda config --set solver libmamba
+        conda update -y -q conda
+    - name: Install env using main channel
+      if: inputs.raft == 'OFF'
+      shell: bash
+      run: |
+        conda install -y -q python=3.11 cmake make swig=4.0.2 mkl=2023 mkl-devel=2023 numpy scipy pytest gxx_linux-64 sysroot_linux-64
+    - name: Install env using conda-forge channel
+      if: inputs.raft == 'ON'
+      shell: bash
+      run: |
+        conda install -y -q python=3.11 cmake make swig=4.0.2 mkl=2023 mkl-devel=2023 numpy scipy pytest gxx_linux-64 sysroot_linux-64=2.28 libraft cuda-version=11.8 cuda-toolkit -c rapidsai-nightly -c "nvidia/label/cuda-11.8.0" -c conda-forge
+    - name: Install CUDA
+      if: inputs.gpu == 'ON' && inputs.raft == 'OFF'
+      shell: bash
+      run: |
+        conda install -y -q cuda-toolkit -c "nvidia/label/cuda-11.8.0"
+    - name: Build all targets
+      shell: bash
+      run: |
+        eval "$(conda shell.bash hook)"
+        conda activate
+        cmake -B build \
+              -DBUILD_TESTING=ON \
+              -DBUILD_SHARED_LIBS=ON \
+              -DFAISS_ENABLE_GPU=${{ inputs.gpu }} \
+              -DFAISS_ENABLE_RAFT=${{ inputs.raft }} \
+              -DFAISS_OPT_LEVEL=${{ inputs.opt_level }} \
+              -DFAISS_ENABLE_C_API=ON \
+              -DPYTHON_EXECUTABLE=$CONDA/bin/python \
+              -DCMAKE_BUILD_TYPE=Release \
+              -DBLA_VENDOR=Intel10_64_dyn \
+              -DCMAKE_CUDA_FLAGS="-gencode arch=compute_75,code=sm_75" \
+              .
+        make -k -C build -j$(nproc)
+    - name: C++ tests
+      shell: bash
+      run: |
+        export GTEST_OUTPUT="xml:$(realpath .)/test-results/googletest/"
+        make -C build test
+    - name: Install Python extension
+      shell: bash
+      working-directory: build/faiss/python
+      run: |
+        $CONDA/bin/python setup.py install
+    - name: Install pytest
+      shell: bash
+      run: |
+        conda install -y pytest
+        echo "$CONDA/bin" >> $GITHUB_PATH
+    - name: Python tests (CPU only)
+      if: inputs.gpu == 'OFF'
+      shell: bash
+      run: |
+        conda install -y -q pytorch -c pytorch
+        pytest --junitxml=test-results/pytest/results.xml tests/test_*.py
+        pytest --junitxml=test-results/pytest/results-torch.xml tests/torch_*.py
+    - name: Python tests (CPU + GPU)
+      if: inputs.gpu == 'ON'
+      shell: bash
+      run: |
+        conda install -y -q pytorch pytorch-cuda=11.8 -c pytorch -c nvidia/label/cuda-11.8.0
+        pytest --junitxml=test-results/pytest/results.xml tests/test_*.py
+        pytest --junitxml=test-results/pytest/results-torch.xml tests/torch_*.py
+        cp tests/common_faiss_tests.py faiss/gpu/test
+        pytest --junitxml=test-results/pytest/results-gpu.xml faiss/gpu/test/test_*.py
+        pytest --junitxml=test-results/pytest/results-gpu-torch.xml faiss/gpu/test/torch_*.py
+    - name: Test avx2 loading
+      if: inputs.opt_level == 'avx2'
+      shell: bash
+      run: |
+        FAISS_DISABLE_CPU_FEATURES=AVX2 LD_DEBUG=libs $CONDA/bin/python -c "import faiss" 2>&1 | grep faiss.so
+        LD_DEBUG=libs $CONDA/bin/python -c "import faiss" 2>&1 | grep faiss_avx2.so
+    - name: Upload test results
+      uses: actions/upload-artifact@v4.3.1
+      with:
+        name: test-results-${{ inputs.opt_level }}-${{ inputs.gpu }}-${{ inputs.raft }}
+        path: test-results
diff --git a/.github/actions/build_conda/action.yml b/.github/actions/build_conda/action.yml
new file mode 100644
index 0000000000..7e4510b4b2
--- /dev/null
+++ b/.github/actions/build_conda/action.yml
@@ -0,0 +1,98 @@
+name: Build conda
+description: Build conda
+inputs:
+  label:
+    description: "Label"
+    default: ""
+    required: false
+  cuda:
+    description: "cuda"
+    default: ""
+    required: false
+  raft:
+    description: "raft"
+    default: ""
+    required: false
+  compiler_version:
+    description: "compiler_version"
+    default: ""
+    required: false
+runs:
+  using: composite
+  steps:
+    - name: Choose shell
+      shell: bash
+      id: choose_shell
+      run: |
+        # if runner.os != 'Windows' use bash, else use pwsh
+        if [ "${{ runner.os }}" != "Windows" ]; then
+          echo "shell=bash" >> "$GITHUB_OUTPUT"
+        else
+          echo "shell=pwsh" >> "$GITHUB_OUTPUT"
+        fi
+    - name: Setup miniconda
+      uses: conda-incubator/setup-miniconda@v3.0.3
+      with:
+        python-version: '3.11'
+        miniconda-version:  latest
+    - name: Install conda build tools
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      run: |
+        # conda config --set solver libmamba
+        # conda config --set verbosity 3
+        conda update -y -q conda
+        conda install -y -q conda-build
+    - name: Enable anaconda uploads
+      if: inputs.label != ''
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      env:
+        PACKAGE_TYPE: inputs.label
+      run: |
+        conda install -y -q anaconda-client
+        conda config --set anaconda_upload yes
+    - name: Conda build (CPU)
+      if: inputs.label == '' && inputs.cuda == ''
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      working-directory: conda
+      run: |
+        conda build faiss --python 3.11 -c pytorch
+    - name: Conda build (CPU) w/ anaconda upload
+      if: inputs.label != '' && inputs.cuda == ''
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      working-directory: conda
+      env:
+        PACKAGE_TYPE: inputs.label
+      run: |
+        conda build faiss --user pytorch --label ${{ inputs.label }} -c pytorch
+    - name: Conda build (GPU)
+      if: inputs.label == '' && inputs.cuda != '' && inputs.raft == ''
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      working-directory: conda
+      run: |
+        conda build faiss-gpu --variants '{ "cudatoolkit": "${{ inputs.cuda }}", "c_compiler_version": "${{ inputs.compiler_version }}", "cxx_compiler_version": "${{ inputs.compiler_version }}" }' \
+            -c pytorch -c nvidia/label/cuda-${{ inputs.cuda }} -c nvidia
+    - name: Conda build (GPU) w/ anaconda upload
+      if: inputs.label != '' && inputs.cuda != '' && inputs.raft == ''
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      working-directory: conda
+      env:
+        PACKAGE_TYPE: inputs.label
+      run: |
+        conda build faiss-gpu --variants '{ "cudatoolkit": "${{ inputs.cuda }}", "c_compiler_version": "${{ inputs.compiler_version }}", "cxx_compiler_version": "${{ inputs.compiler_version }}" }' \
+            --user pytorch --label ${{ inputs.label }} -c pytorch -c nvidia/label/cuda-${{ inputs.cuda }} -c nvidia
+    - name: Conda build (GPU w/ RAFT)
+      if: inputs.label == '' && inputs.cuda != '' && inputs.raft != ''
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      working-directory: conda
+      run: |
+        conda build faiss-gpu-raft --variants '{ "cudatoolkit": "${{ inputs.cuda }}", "c_compiler_version": "${{ inputs.compiler_version }}", "cxx_compiler_version": "${{ inputs.compiler_version }}" }' \
+            -c pytorch -c nvidia/label/cuda-${{ inputs.cuda }} -c nvidia -c rapidsai -c rapidsai-nightly -c conda-forge
+    - name: Conda build (GPU w/ RAFT) w/ anaconda upload
+      if: inputs.label != '' && inputs.cuda != '' && inputs.raft != ''
+      shell: ${{ steps.choose_shell.outputs.shell }}
+      working-directory: conda
+      env:
+        PACKAGE_TYPE: inputs.label
+      run: |
+        conda build faiss-gpu-raft --variants '{ "cudatoolkit": "${{ inputs.cuda }}", "c_compiler_version": "${{ inputs.compiler_version }}", "cxx_compiler_version": "${{ inputs.compiler_version }}" }' \
+            --user pytorch --label ${{ inputs.label }} -c pytorch -c nvidia/label/cuda-${{ inputs.cuda }} -c nvidia -c rapidsai -c rapidsai-nightly -c conda-forge
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000000..03c19f1642
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,197 @@
+name: Build
+on:
+  workflow_dispatch:
+  pull_request:
+    branches:
+      - main
+  push:
+    tags:
+      - 'v*'
+env:
+  OMP_NUM_THREADS: '10'
+  MKL_THREADING_LAYER: GNU
+jobs:
+  format:
+    if: false # disabled during migration to GitHub Actions
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - name: Install clang-format
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y git-core clang-format-11
+      - name: Verify clang-format
+        run: |
+            git ls-files | grep -E  '\.(cpp|h|cu|cuh)$' | xargs clang-format-11 -i
+            if git diff --quiet; then
+              echo "Formatting OK!"
+            else
+              echo "Formatting not OK!"
+              echo "------------------"
+              git --no-pager diff --color
+              exit 1
+            fi
+  linux-x86_64-cmake:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_cmake
+  linux-x86_64-AVX2-cmake:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_cmake
+        with:
+          opt_level: avx2
+  linux-x86_64-AVX512-cmake:
+    if: false # disabled during migration to GitHub Actions
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_cmake
+        with:
+          opt_level: avx512
+  linux-x86_64-GPU-cmake:
+    if: false # disabled during migration to GitHub Actions
+    needs: linux-x86_64-AVX2-cmake
+    runs-on: 4-core-ubuntu-gpu-t4
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_cmake
+        with:
+          gpu: ON
+  linux-x86_64-GPU-w-RAFT-cmake:
+    if: false # disabled during migration to GitHub Actions
+    needs: linux-x86_64-GPU-cmake
+    runs-on: 4-core-ubuntu-gpu-t4
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_cmake
+        with:
+          gpu: ON
+          raft: ON
+  linux-x86_64-conda:
+    if: false # disabled during migration to GitHub Actions
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+  windows-x86_64-conda:
+    if: false # disabled during migration to GitHub Actions
+    runs-on: windows-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+  linux-arm64-conda:
+    if: false # disabled during migration to GitHub Actions
+    runs-on: 4-core-arm
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+  linux-x86_64-packages:
+    if: false # disabled during migration to GitHub Actions
+    #if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+        with:
+          label: main
+  linux-x86_64-GPU-packages-CUDA-11-4-4:
+    if: false # disabled during migration to GitHub Actions
+    #if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    runs-on: 4-core-ubuntu-gpu-t4
+    env:
+      CUDA_ARCHS: "60-real;61-real;62-real;70-real;72-real;75-real;80;86-real"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+        with:
+          label: main
+          cuda: "11.4.4"
+          compiler_version: "11.2"
+  linux-x86_64-GPU-RAFT-packages-CUDA11-8-0:
+    if: false # disabled during migration to GitHub Actions
+    #if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    runs-on: 4-core-ubuntu-gpu-t4
+    env:
+      CUDA_ARCHS: "70-real;72-real;75-real;80;86-real"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+        with:
+          label: main
+          raft: "ON"
+          cuda: "11.8.0"
+          compiler_version: "11.2"
+  linux-x86_64-GPU-packages-CUDA-12-1-1:
+    if: false # disabled during migration to GitHub Actions
+    #if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    runs-on: 4-core-ubuntu-gpu-t4
+    env:
+      CUDA_ARCHS: "70-real;72-real;75-real;80;86-real"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+        with:
+          label: main
+          cuda: "12.1.1"
+          compiler_version: "11.2"
+  linux-x86_64-GPU-RAFT-packages-CUDA12-1-1:
+    if: false # disabled during migration to GitHub Actions
+    #if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    runs-on: 4-core-ubuntu-gpu-t4
+    env:
+      CUDA_ARCHS: "70-real;72-real;75-real;80;86-real"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+        with:
+          label: main
+          raft: "ON"
+          cuda: "12.1.1"
+          compiler_version: "11.2"
+  windows-x86_64-packages:
+    if: false # disabled during migration to GitHub Actions
+    #if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    runs-on: windows-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+        with:
+          label: main
+  OSX-arm64-packages:
+    if: false # disabled during migration to GitHub Actions
+    #if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    runs-on: macos-13
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+        with:
+          label: main
+  linux-arm64-packages:
+    if: false # disabled during migration to GitHub Actions
+    #if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    runs-on: 4-core-arm
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4.1.1
+      - uses: ./.github/actions/build_conda
+        with:
+          label: main