diff --git a/.github/workflows/build-pyxirr.yml b/.github/workflows/build-pyxirr.yml
new file mode 100644
index 000000000..e77c3fbc4
--- /dev/null
+++ b/.github/workflows/build-pyxirr.yml
@@ -0,0 +1,157 @@
+# SPDX-FileCopyrightText: 2026 The RISE Project
+# SPDX-License-Identifier: MIT
+---
+# This workflow is based on the `linux` job of
+# https://github.com/Anexen/pyxirr/blob/v0.10.8/.github/workflows/ci.yaml
+name: Build pyxirr wheels (riscv64)
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'pyxirr version to build (git tag without leading v, e.g. 0.10.8)'
+        required: true
+        default: '0.10.8'
+  pull_request:
+    paths:
+      - '.github/workflows/build-pyxirr.yml'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ inputs.version || '0.10.8' }}-${{ 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 0.10.8 there.
+  PYXIRR_VERSION: ${{ inputs.version || '0.10.8' }}
+  MANYLINUX_RISCV64_IMAGE: quay.io/pypa/manylinux_2_39_riscv64
+
+jobs:
+  setup:
+    uses: $/.github/workflows/_setup.yml
+
+  build_wheels:
+    needs: [setup]
+    name: Build pyxirr ${{ inputs.version || '0.10.8' }} ${{ matrix.tag }}-manylinux_riscv64
+    runs-on: ubuntu-24.04-riscv
+    timeout-minutes: 60
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          # pyxirr's [tool.maturin] features only lists "extension"
+          # (pyo3/extension-module); upstream's own release job additionally
+          # passes --features extension,abi (pyo3/abi3-py37) on the maturin
+          # command line to get the single cp37-abi3 wheel it publishes to
+          # PyPI, so we restate the same flags here (gotcha 155). Upstream
+          # ships no free-threaded wheel, so the matrix stays a single entry
+          # built once at our cp312 floor and re-tested on cp313/cp314.
+          - tag: cp37-abi3
+            build: >-
+              cp312-manylinux_riscv64 cp313-manylinux_riscv64
+              cp314-manylinux_riscv64
+            features: --features extension,abi
+
+    steps:
+      - name: Checkout pyxirr v${{ env.PYXIRR_VERSION }}
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          repository: Anexen/pyxirr
+          ref: v${{ env.PYXIRR_VERSION }}
+          persist-credentials: false
+
+      - name: Stage the riscv64 smoke tests
+        # Upstream's tests/ directory holds only Rust integration tests
+        # (exercised by `cargo test` in ci.yaml), no Python-level suite ships
+        # in the checkout or the sdist. This mirrors the README's examples
+        # against the compiled extension.
+        run: |
+          cat > tests/test_riscv64_smoke.py <<'EOF'
+          from datetime import date
+
+          import numpy as np
+          import pytest
+          from pyxirr import DayCount, fv, irr, is_conventional_cash_flow, npv, xirr, xnpv
+
+
+          def test_extension_is_compiled():
+              from pyxirr import _pyxirr
+
+              assert _pyxirr.__file__.endswith(".so"), _pyxirr.__file__
+
+
+          def test_irr():
+              assert irr([-100, 39, 59, 55, 20]) == pytest.approx(0.28094842)
+
+
+          def test_xirr_dates_and_amounts():
+              dates = [date(2020, 1, 1), date(2021, 1, 1), date(2022, 1, 1)]
+              amounts = [-1000, 750, 500]
+              assert xirr(dates, amounts) == pytest.approx(0.17500926)
+
+
+          def test_xirr_string_dates_and_dict():
+              assert xirr(["2020-01-01", "2021-01-01"], [-1000, 1200]) == pytest.approx(0.19940237)
+              assert xirr(dict(zip(
+                  ["2020-01-01", "2021-01-01"], [-1000, 1200],
+              ))) == pytest.approx(0.19940237)
+
+
+          def test_npv_and_xnpv():
+              assert npv(0.1, [-100, 60, 60, 60]) == pytest.approx(49.21111946)
+              assert xnpv(0.1, ["2020-01-01", "2021-01-01"], [-100, 110]) == pytest.approx(-0.02610897)
+
+
+          def test_fv_broadcasts_over_numpy_arrays():
+              rates = np.array([0.05, 0.1])
+              result = fv(rates, 10, -100, 0)
+              assert result == pytest.approx([1257.78925, 1593.7424601])
+
+
+          def test_day_count_convention():
+              assert xirr(
+                  ["2020-01-01", "2021-01-01"], [-1000, 1200],
+                  day_count=DayCount.ACT_360,
+              ) == pytest.approx(0.19641870)
+
+
+          def test_is_conventional_cash_flow():
+              assert is_conventional_cash_flow([-100, 50, 50, 50])
+              assert not is_conventional_cash_flow([-100, 50, -20, 80])
+          EOF
+
+      - name: Build and test wheels
+        uses: pypa/cibuildwheel@1828c10ab37f080699c7b81cea34097c684a7074  # v4.2.0
+        env:
+          CIBW_ARCHS: riscv64
+          CIBW_BUILD: ${{ matrix.build }}
+          CIBW_MANYLINUX_RISCV64_IMAGE: ${{ env.MANYLINUX_RISCV64_IMAGE }}
+          # pyxirr ships no [tool.cibuildwheel], so the Rust toolchain its
+          # maturin backend needs is installed in-container here.
+          CIBW_BEFORE_ALL_LINUX: >-
+            curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+          CIBW_ENVIRONMENT_LINUX: >-
+            PATH="$PATH:$HOME/.cargo/bin"
+            MATURIN_PEP517_ARGS="${{ matrix.features }}"
+            PIP_EXTRA_INDEX_URL=https://pypi.riseproject.dev/simple/
+            PIP_ONLY_BINARY=numpy
+          CIBW_TEST_REQUIRES: pytest numpy
+          CIBW_TEST_COMMAND: python -m pytest -vv {project}/tests/test_riscv64_smoke.py
+
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: pyxirr-${{ env.PYXIRR_VERSION }}-${{ matrix.tag }}-manylinux_riscv64
+          path: ./wheelhouse/*.whl
+          if-no-files-found: error
+
+  publish:
+    name: Publish pyxirr ${{ inputs.version || '0.10.8' }}
+    needs: [setup, build_wheels]
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: $/.github/workflows/_publish-wheel.yml
+    with:
+      artifact-pattern: pyxirr-${{ inputs.version || '0.10.8' }}-*-manylinux_riscv64