diff --git a/.github/workflows/build-stream-inflate.yml b/.github/workflows/build-stream-inflate.yml
new file mode 100644
index 000000000..20e263599
--- /dev/null
+++ b/.github/workflows/build-stream-inflate.yml
@@ -0,0 +1,88 @@
+# SPDX-FileCopyrightText: 2026 The RISE Project
+# SPDX-License-Identifier: MIT
+---
+# Based on the `build-linux` job of
+# https://github.com/michalc/stream-inflate/blob/v0.0.43/.github/workflows/build-source-package-and-wheels.yml
+name: Build stream-inflate wheels (riscv64)
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'stream-inflate version to build (git tag without leading v, e.g. 0.0.43)'
+        required: true
+        default: '0.0.43'
+  pull_request:
+    paths:
+      - '.github/workflows/build-stream-inflate.yml'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ inputs.version || '0.0.43' }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read  # to fetch code (actions/checkout)
+
+env:
+  STREAM_INFLATE_VERSION: ${{ inputs.version || '0.0.43' }}
+  MANYLINUX_RISCV64_IMAGE: quay.io/pypa/manylinux_2_39_riscv64
+
+jobs:
+  setup:
+    uses: $/.github/workflows/_setup.yml
+
+  build_wheels:
+    needs: [setup]
+    name: Build stream-inflate ${{ inputs.version || '0.0.43' }} ${{ matrix.python }}-manylinux_riscv64
+    runs-on: ubuntu-24.04-riscv
+    # test_stream_inflate.py's parametrized fuzz suite (1956 cases, up to 8MB of
+    # byte-chunked data) needs up to ~2h15m here.
+    timeout-minutes: 240
+    strategy:
+      fail-fast: false
+      matrix:
+        python: ["cp312", "cp313", "cp314", "cp314t"]
+
+    steps:
+      - name: Checkout stream-inflate v${{ env.STREAM_INFLATE_VERSION }}
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          repository: michalc/stream-inflate
+          ref: v${{ env.STREAM_INFLATE_VERSION }}
+          persist-credentials: false
+
+      # Committed source carries a 0.0.0.dev0 placeholder that upstream's own
+      # release workflow sed-replaces with the tag name; reproduce it verbatim.
+      - name: Set version from git tag
+        run: |
+          sed -i "s/0\.0\.0\.dev0/v${{ env.STREAM_INFLATE_VERSION }}/g" pyproject.toml setup.py
+
+      - uses: pypa/cibuildwheel@1828c10ab37f080699c7b81cea34097c684a7074  # v4.2.0
+        env:
+          CIBW_ARCHS: riscv64
+          CIBW_BUILD: ${{ matrix.python }}-manylinux_riscv64
+          CIBW_MANYLINUX_RISCV64_IMAGE: ${{ env.MANYLINUX_RISCV64_IMAGE }}
+          # Cython, a build-system.requires dep, has no riscv64 wheel on public
+          # PyPI; resolve it from our registry instead of compiling it in-container.
+          CIBW_ENVIRONMENT: PIP_EXTRA_INDEX_URL=https://pypi.riseproject.dev/simple/
+          CIBW_TEST_SOURCES: test_stream_inflate.py fixtures
+          CIBW_TEST_REQUIRES: pytest
+          CIBW_TEST_COMMAND: >-
+            python -c "import stream_inflate as m; assert m.__file__.endswith('.so'), m.__file__" &&
+            python -m pytest test_stream_inflate.py -v
+
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: stream-inflate-${{ env.STREAM_INFLATE_VERSION }}-${{ matrix.python }}-manylinux_riscv64
+          path: ./wheelhouse/*.whl
+          if-no-files-found: error
+
+  publish:
+    name: Publish stream-inflate ${{ inputs.version || '0.0.43' }}
+    needs: [setup, build_wheels]
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: $/.github/workflows/_publish-wheel.yml
+    with:
+      artifact-pattern: stream-inflate-${{ inputs.version || '0.0.43' }}-*-manylinux_riscv64