diff --git a/.github/workflows/build-unicode-segmentation-rs.yml b/.github/workflows/build-unicode-segmentation-rs.yml
new file mode 100644
index 000000000..c7091c3c1
--- /dev/null
+++ b/.github/workflows/build-unicode-segmentation-rs.yml
@@ -0,0 +1,107 @@
+# SPDX-FileCopyrightText: 2026 The RISE Project
+# SPDX-License-Identifier: MIT
+---
+# Based on upstream's own wheel builder (`linux` job):
+#   https://github.com/WeblateOrg/unicode-segmentation-rs/blob/v0.3.3/.github/workflows/ci.yml
+name: Build unicode-segmentation-rs wheels (riscv64)
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'unicode-segmentation-rs version to build (git tag without leading v, e.g. 0.3.3)'
+        required: true
+        default: '0.3.3'
+  pull_request:
+    paths:
+      - '.github/workflows/build-unicode-segmentation-rs.yml'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ inputs.version || '0.3.3' }}-${{ 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 0.3.3 there.
+  UNICODE_SEGMENTATION_RS_VERSION: ${{ inputs.version || '0.3.3' }}
+  MANYLINUX_RISCV64_IMAGE: quay.io/pypa/manylinux_2_39_riscv64
+
+jobs:
+  setup:
+    uses: $/.github/workflows/_setup.yml
+
+  build_wheels:
+    needs: [setup]
+    name: Build unicode-segmentation-rs ${{ inputs.version || '0.3.3' }} ${{ matrix.python }}-manylinux_riscv64
+    runs-on: ubuntu-24.04-riscv
+    timeout-minutes: 60
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          # Cargo.toml enables pyo3's abi3-py310 unconditionally, so one abi3
+          # wheel serves every GIL-ful interpreter from cp310; pyo3 disables
+          # abi3 under Py_GIL_DISABLED, so cp314t gets its own per-interpreter
+          # wheel, and the opt-in `abi3t` feature (pyo3/abi3t-py315) gives
+          # cp315t+ a forward-compatible cp315-abi3.abi3t wheel -- matching the
+          # exact three-wheel split upstream publishes to PyPI.
+          - python: cp310
+            features: ''
+          - python: cp314t
+            features: ''
+          - python: cp315t
+            features: '--features abi3t'
+
+    steps:
+      - name: Checkout unicode-segmentation-rs v${{ env.UNICODE_SEGMENTATION_RS_VERSION }}
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          repository: WeblateOrg/unicode-segmentation-rs
+          ref: v${{ env.UNICODE_SEGMENTATION_RS_VERSION }}
+          persist-credentials: false
+
+      - name: Build and test wheel
+        uses: pypa/cibuildwheel@1828c10ab37f080699c7b81cea34097c684a7074  # v4.2.0
+        with:
+          output-dir: wheelhouse/
+          only: ${{ matrix.python }}-manylinux_riscv64
+        env:
+          CIBW_MANYLINUX_RISCV64_IMAGE: ${{ env.MANYLINUX_RISCV64_IMAGE }}
+          # unicode-segmentation-rs ships no [tool.cibuildwheel], so the Rust
+          # toolchain its maturin backend needs is installed in-container here.
+          CIBW_BEFORE_ALL_LINUX: >-
+            curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+          CIBW_ENVIRONMENT_LINUX: >-
+            PATH="$PATH:$HOME/.cargo/bin"
+            MATURIN_PEP517_ARGS="${{ matrix.features }}"
+          # The cp315-abi3.abi3t wheel exports its multi-phase init entry point as
+          # PyModExport_unicode_segmentation_rs (defined in the extension itself, not
+          # imported); cibuildwheel's bundled abi3audit doesn't recognize that name and
+          # flags it as a non-abi3 symbol (gotcha 134), reproducing on upstream's own
+          # published wheel.
+          CIBW_AUDIT_COMMAND: ''
+          CIBW_TEST_REQUIRES: pytest
+          CIBW_TEST_SOURCES: tests
+          CIBW_TEST_COMMAND: >-
+            python -c "import unicode_segmentation_rs as m, importlib.metadata as md;
+            assert m.unicode_segmentation_rs.__file__.endswith('.so'), m.unicode_segmentation_rs.__file__;
+            assert any(str(p).endswith('licenses/LICENSE') for p in md.files('unicode-segmentation-rs'))" &&
+            python -m pytest -v tests
+
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: unicode-segmentation-rs-${{ env.UNICODE_SEGMENTATION_RS_VERSION }}-${{ matrix.python }}-manylinux_riscv64
+          path: wheelhouse/*.whl
+          if-no-files-found: error
+
+  publish:
+    name: Publish unicode-segmentation-rs ${{ inputs.version || '0.3.3' }}
+    needs: [setup, build_wheels]
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: $/.github/workflows/_publish-wheel.yml
+    with:
+      artifact-pattern: unicode-segmentation-rs-${{ inputs.version || '0.3.3' }}-*-manylinux_riscv64