vtracer: add build-vtracer.yml for riscv64 wheels

.github/workflows/build-vtracer.yml

@@ -0,0 +1,99 @@
+# SPDX-FileCopyrightText: 2026 The RISE Project
+# SPDX-License-Identifier: MIT
+---
+# This workflow is based on the `linux` job of
+# https://github.com/visioncortex/vtracer/blob/0.6.15/.github/workflows/python.yml
+name: Build vtracer wheels (riscv64)
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'vtracer version to build (git tag, e.g. 0.6.15)'
+        required: true
+        default: '0.6.15'
+  pull_request:
+    paths:
+      - '.github/workflows/build-vtracer.yml'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ inputs.version || '0.6.15' }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read  # to fetch code (actions/checkout)
+
+env:
+  # `inputs.version` is empty on pull_request events; default to 0.6.15 there.
+  VTRACER_VERSION: ${{ inputs.version || '0.6.15' }}
+  MANYLINUX_RISCV64_IMAGE: quay.io/pypa/manylinux_2_39_riscv64
+
+jobs:
+  setup:
+    uses: $/.github/workflows/_setup.yml
+
+  build_wheels:
+    needs: [setup]
+    name: Build vtracer ${{ inputs.version || '0.6.15' }} ${{ matrix.python }}-manylinux_riscv64
+    runs-on: ubuntu-24.04-riscv
+    timeout-minutes: 60
+    strategy:
+      fail-fast: false
+      matrix:
+        # pyo3 0.19.2, no abi3 feature, so every interpreter needs its own
+        # build. cp314 segfaults on the first string crossing the FFI
+        # boundary - this pyo3 predates CPython 3.14's changed Unicode
+        # object layout (gotcha 322) - and cp314t is dropped too, since the
+        # same pyo3 predates Py_GIL_DISABLED entirely (gotcha 306).
+        python: ["cp312", "cp313"]
+
+    steps:
+      - name: Checkout vtracer ${{ env.VTRACER_VERSION }}
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          repository: visioncortex/vtracer
+          ref: ${{ env.VTRACER_VERSION }}
+          persist-credentials: false
+
+      - name: Build and test wheel
+        uses: pypa/cibuildwheel@1828c10ab37f080699c7b81cea34097c684a7074  # v4.2.0
+        with:
+          package-dir: cmdapp
+          output-dir: wheelhouse/
+        env:
+          CIBW_BUILD: ${{ matrix.python }}-manylinux_riscv64
+          CIBW_MANYLINUX_RISCV64_IMAGE: ${{ env.MANYLINUX_RISCV64_IMAGE }}
+          # vtracer's pyproject.toml carries no [tool.cibuildwheel], so the
+          # Rust toolchain its maturin backend needs is installed in-container
+          # here.
+          CIBW_BEFORE_ALL_LINUX: >-
+            curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+          CIBW_ENVIRONMENT_LINUX: PATH="$PATH:$HOME/.cargo/bin"
+          # Upstream ships no Python test suite at all. Exercise the
+          # extension for real instead: convert a small two-colour raster to
+          # SVG and check it actually traced a path, not just the README's
+          # bare import.
+          CIBW_TEST_COMMAND: >-
+            python -c "import vtracer.vtracer as ext, vtracer;
+            assert ext.__file__.endswith('.so'), ext.__file__;
+            w, h = 10, 10;
+            pixels = [(255, 0, 0, 255) if x < w // 2 else (0, 0, 255, 255) for y in range(h) for x in range(w)];
+            svg = vtracer.convert_pixels_to_svg(pixels, (w, h));
+            assert isinstance(svg, str) and '<svg' in svg and '<path' in svg, svg
+            "
+
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: vtracer-${{ env.VTRACER_VERSION }}-${{ matrix.python }}-manylinux_riscv64
+          path: wheelhouse/*.whl
+          if-no-files-found: error
+
+  publish:
+    name: Publish vtracer ${{ inputs.version || '0.6.15' }}
+    needs: [setup, build_wheels]
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: $/.github/workflows/_publish-wheel.yml
+    with:
+      artifact-pattern: vtracer-${{ inputs.version || '0.6.15' }}-*-manylinux_riscv64