diff --git a/.github/workflows/build-no-defaults.yml b/.github/workflows/build-no-defaults.yml
new file mode 100644
index 00000000000..4cd0336c17f
--- /dev/null
+++ b/.github/workflows/build-no-defaults.yml
@@ -0,0 +1,207 @@
+# SPDX-FileCopyrightText: 2026 The RISE Project
+# SPDX-License-Identifier: MIT
+---
+# This workflow is based on the `build-wheels` job of
+# https://github.com/adamtheturtle/no-defaults/blob/2026.9.1/.github/workflows/release.yml
+name: Build no-defaults wheels (riscv64)
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'Version glob to (re)build; empty builds every version of docs/packages/no-defaults.yaml not released yet'
+        required: false
+        default: ''
+  pull_request:
+    branches: [main]
+    paths:
+      - '.github/workflows/build-no-defaults.yml'
+      - 'docs/packages/no-defaults.yaml'
+  push:
+    branches: [main]
+    paths:
+      - '.github/workflows/build-no-defaults.yml'
+      - 'docs/packages/no-defaults.yaml'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read  # to fetch code (actions/checkout)
+
+jobs:
+  setup:
+    uses: $/.github/workflows/_setup.yml
+    with:
+      package: no-defaults
+      version: ${{ inputs.version }}
+
+  build_wheel:
+    needs: [setup]
+    if: needs.setup.outputs.versions != '[]'
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ${{ fromJSON(needs.setup.outputs.versions) }}
+    name: Build no-defaults ${{ matrix.version }} manylinux_riscv64
+    runs-on: ubuntu-24.04-riscv
+    timeout-minutes: 360
+
+    env:
+      NO_DEFAULTS_VERSION: ${{ matrix.version }}
+
+    steps:
+      # Upstream tags same-day re-releases as `<date>-post.<N>` (wheel version `<date>.post<N>`).
+      - name: Resolve git tag
+        id: tag
+        run: echo "ref=${NO_DEFAULTS_VERSION/.post/-post.}" >> "$GITHUB_OUTPUT"
+
+      - name: Checkout no-defaults ${{ steps.tag.outputs.ref }}
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          repository: adamtheturtle/no-defaults
+          ref: ${{ steps.tag.outputs.ref }}
+          persist-credentials: false
+
+      # No musl target: rustup.rs ships no riscv64 musl toolchain.
+      - name: Build wheel
+        uses: PyO3/maturin-action@e83996d129638aa358a18fbd1dfb82f0b0fb5d3b  # v1.51.0
+        with:
+          command: build
+          target: riscv64gc-unknown-linux-gnu
+          args: --release --out dist
+          manylinux: '2_39'
+          before-script-linux: git config --global --add safe.directory "*"
+
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: no-defaults-${{ env.NO_DEFAULTS_VERSION }}-manylinux_riscv64
+          path: dist/*.whl
+          if-no-files-found: error
+
+  test_wheel:
+    name: Test no-defaults ${{ matrix.version }} on Python ${{ matrix.python-version }}
+    needs: [setup, build_wheel]
+    if: needs.setup.outputs.versions != '[]'
+    runs-on: ubuntu-24.04-riscv
+    timeout-minutes: 30
+    env:
+      NO_DEFAULTS_VERSION: ${{ matrix.version }}
+      UV_PYTHON_PREFERENCE: only-managed
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ${{ fromJSON(needs.setup.outputs.versions) }}
+        python-version: ['3.12', '3.13', '3.14', '3.14t']
+
+    steps:
+      - name: Resolve git tag
+        id: tag
+        run: echo "ref=${NO_DEFAULTS_VERSION/.post/-post.}" >> "$GITHUB_OUTPUT"
+
+      - name: Checkout no-defaults ${{ steps.tag.outputs.ref }} test fixtures
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          repository: adamtheturtle/no-defaults
+          ref: ${{ steps.tag.outputs.ref }}
+          path: upstream
+          sparse-checkout: tests/fixtures
+          persist-credentials: false
+
+      - name: Download wheel
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c  # v8.0.1
+        with:
+          name: no-defaults-${{ env.NO_DEFAULTS_VERSION }}-manylinux_riscv64
+          path: dist
+
+      - name: Install Python
+        uses: astral-sh/setup-uv@20cfd1bf945f4377ade1205e4dbc17946fc9a30d  # v10.0.1
+        with:
+          python-version: ${{ matrix.python-version }}
+          activate-environment: true
+          enable-cache: false
+
+      - name: Install wheel
+        run: uv pip install --reinstall --find-links dist "no-defaults==${NO_DEFAULTS_VERSION}"
+
+      # Upstream's tests are a Rust integration suite (`cargo test`) that is never packaged;
+      # drive the installed binary, which requires the `ty` it depends on, through the
+      # suite's `real_project_uses_per_file_configuration` and
+      # `fix_updates_call_sites_across_files` cases instead.
+      - name: Test wheel
+        run: |
+          set -euo pipefail
+          no-defaults --version
+          ty version
+
+          set +e
+          no-defaults --output-format json upstream/tests/fixtures/real_project > report.json
+          rc=$?
+          set -e
+          [ "$rc" -eq 1 ]
+          python - <<'PY'
+          import json
+          diagnostics = json.load(open("report.json"))
+          text = json.dumps(diagnostics)
+          assert len(diagnostics) == 2, diagnostics
+          assert "_private" in text and "helper" in text, text
+          assert "function `public`" not in text, text
+          PY
+
+          work=$(mktemp -d)
+          cat > "$work/api.py" <<'PY'
+          from dataclasses import dataclass, field
+
+          def connect(host, timeout=30, *, retries=3):
+              return host
+
+          @dataclass
+          class Job:
+              name: str
+              tags: list = field(default_factory=list)
+
+          class Client:
+              def fetch(self, url, verify=True):
+                  return url
+
+              def twice(self, url):
+                  return self.fetch(url)
+          PY
+          cat > "$work/caller.py" <<'PY'
+          import api
+
+          api.connect("h")
+          api.connect("h", 5, retries=1)
+          api.Job("j")
+          PY
+
+          no-defaults --fix "$work" | tee fix.log
+          grep -q 'Updated 3 call sites.' fix.log
+          cat > expected.py <<'PY'
+          import api
+
+          api.connect("h", timeout=30, retries=3)
+          api.connect("h", 5, retries=1)
+          api.Job("j", tags=[])
+          PY
+          diff -u expected.py "$work/caller.py"
+          grep -q 'self.fetch(url, verify=True)' "$work/api.py"
+          no-defaults "$work"
+
+  publish:
+    name: Publish no-defaults ${{ matrix.version }}
+    needs: [setup, build_wheel, test_wheel]
+    if: needs.setup.outputs.versions != '[]'
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ${{ fromJSON(needs.setup.outputs.versions) }}
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: $/.github/workflows/_publish-wheel.yml
+    secrets:
+      app-private-key: ${{ secrets.RISEPROJECT_APP_PRIVATE_KEY }}
+    with:
+      artifact-pattern: no-defaults-${{ matrix.version }}-manylinux_riscv64
diff --git a/docs/packages/no-defaults.yaml b/docs/packages/no-defaults.yaml
new file mode 100644
index 00000000000..8830ceffe6c
--- /dev/null
+++ b/docs/packages/no-defaults.yaml
@@ -0,0 +1,5 @@
+package-name: no-defaults
+source-code: https://github.com/adamtheturtle/no-defaults
+license: MIT
+versions:
+- version: 2026.9.1