diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000..b8cfc26
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,20 @@
+version: 2
+
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly
+      day: saturday
+      time: "17:30"
+      timezone: Asia/Kolkata
+    open-pull-requests-limit: 5
+    groups:
+      actions-minor-patch:
+        patterns:
+          - "*"
+        update-types:
+          - minor
+          - patch
+    commit-message:
+      prefix: update
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
new file mode 100644
index 0000000..d0e1e5d
--- /dev/null
+++ b/.github/workflows/checks.yml
@@ -0,0 +1,171 @@
+name: Checks
+
+on:
+  merge_group:
+  pull_request:
+    branches: [main, gui]
+  push:
+    branches: [main, actions, gui, py]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: checks-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  shell:
+    name: Shell / ${{ matrix.name }}
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 10
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: Linux
+            os: ubuntu-latest
+            language: sh
+          - name: macOS
+            os: macos-latest
+            language: zsh
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Check Linux script
+        if: matrix.language == 'sh'
+        run: |
+          sh -n sys/linux/clean
+          shellcheck --shell=dash --severity=warning --exclude=SC1007 sys/linux/clean
+          sys/linux/clean --self-test
+
+      - name: Check macOS script
+        if: matrix.language == 'zsh'
+        run: |
+          zsh -n sys/macos/clean
+          sys/macos/clean --self-test
+
+  powershell:
+    name: PowerShell / Windows
+    runs-on: windows-latest
+    timeout-minutes: 10
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Install PSScriptAnalyzer
+        shell: pwsh
+        run: Install-Module PSScriptAnalyzer -RequiredVersion 1.25.0 -Scope CurrentUser -Force
+
+      - name: Analyze script
+        shell: pwsh
+        run: |
+          $findings = Invoke-ScriptAnalyzer `
+            -Path sys/windows/clean.ps1 `
+            -Severity Warning, Error `
+            -ExcludeRule PSReviewUnusedParameter, PSUseShouldProcessForStateChangingFunctions, PSUseSingularNouns
+          if ($findings) {
+            $findings | Format-Table -AutoSize
+            exit 1
+          }
+
+      - name: Test script
+        shell: pwsh
+        run: ./sys/windows/clean.ps1 -SelfTest
+
+  python-style:
+    name: Python / style
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@c771a70e6277c0a99b617c7a806ffedaca235ff9 # v9.0.0
+        with:
+          version: "0.11.32"
+          python-version: "3.11"
+          enable-cache: false
+
+      - name: Find and check Python scripts
+        shell: bash
+        run: |
+          mapfile -t python_files < <(
+            git ls-files -- 'bin/_common.py'
+            git grep -Il '^#!/usr/bin/env -S uv run --script' -- '*.py' 'bin/*' || true
+          )
+          if (( ${#python_files[@]} == 0 )); then
+            echo "No Python scripts found"
+            exit 0
+          fi
+          printf 'Checking %s\n' "${python_files[@]}"
+          uvx ruff@0.16.0 format --check --target-version=py311 "${python_files[@]}"
+          uvx ruff@0.16.0 check --output-format=github --target-version=py311 "${python_files[@]}"
+
+  python:
+    name: Python / runtime / ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 10
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@c771a70e6277c0a99b617c7a806ffedaca235ff9 # v9.0.0
+        with:
+          version: "0.11.32"
+          python-version: "3.11"
+          enable-cache: false
+
+      - name: Test dashboard
+        if: hashFiles('dev/gui.py') != ''
+        run: uv run dev/gui.py --self-test
+
+      - name: Test command tools
+        shell: bash
+        run: |
+          found=0
+          while IFS= read -r script; do
+            [[ -n "$script" ]] || continue
+            found=1
+            uv run --script "$script" --self-test
+          done < <(
+            git grep -Il '^#!/usr/bin/env -S uv run --script' -- 'bin/*' || true
+          )
+          (( found )) || echo "No Python command tools found"
+
+  metadata:
+    name: Repository files
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Check Markdown and YAML formatting
+        run: npx --yes prettier@3.9.6 --check '**/*.md' '.github/**/*.{yml,yaml}'
+
+      - name: Check workflows
+        run: go run github.com/rhysd/actionlint/cmd/actionlint@v1.7.12
diff --git a/.github/workflows/quality.yml b/.github/workflows/quality.yml
new file mode 100644
index 0000000..6f57b23
--- /dev/null
+++ b/.github/workflows/quality.yml
@@ -0,0 +1,161 @@
+name: Quality
+
+on:
+  merge_group:
+  pull_request:
+    branches: [main, gui]
+  push:
+    branches: [main, actions, gui, py]
+  schedule:
+    - cron: "17 4 * * 1"
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: quality-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  languages:
+    name: Detect languages
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    outputs:
+      matrix: ${{ steps.detect.outputs.matrix }}
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Build CodeQL matrix
+        id: detect
+        shell: bash
+        run: |
+          if git grep -Il '^#!/usr/bin/env -S uv run --script' -- '*.py' 'bin/*' >/dev/null 2>&1; then
+            echo 'matrix={"include":[{"language":"actions"},{"language":"python"}]}' >> "$GITHUB_OUTPUT"
+          else
+            echo 'matrix={"include":[{"language":"actions"}]}' >> "$GITHUB_OUTPUT"
+          fi
+
+  codeql:
+    name: CodeQL / ${{ matrix.language }}
+    needs: languages
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJSON(needs.languages.outputs.matrix) }}
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@e4fba868fa4b1b91e1fdab776edc8cfbe6e9fb81 # v4.37.3
+        with:
+          languages: ${{ matrix.language }}
+          build-mode: none
+          queries: security-and-quality
+
+      - name: Analyze
+        uses: github/codeql-action/analyze@e4fba868fa4b1b91e1fdab776edc8cfbe6e9fb81 # v4.37.3
+        with:
+          category: /language:${{ matrix.language }}
+
+  dependency-review:
+    name: Dependency review
+    if: github.event_name == 'pull_request'
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    permissions:
+      contents: read
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Review dependency changes
+        uses: actions/dependency-review-action@a1d282b36b6f3519aa1f3fc636f609c47dddb294 # v5.0.0
+        with:
+          fail-on-severity: moderate
+
+  osv:
+    name: OSV scan
+    if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+    uses: google/osv-scanner-action/.github/workflows/osv-scanner-reusable.yml@9a498708959aeaef5ef730655706c5a1df1edbc2 # v2.3.8
+
+  python-audit:
+    name: Python / dependencies
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@c771a70e6277c0a99b617c7a806ffedaca235ff9 # v9.0.0
+        with:
+          version: "0.11.32"
+          python-version: "3.11"
+          enable-cache: false
+
+      - name: Audit script dependencies
+        shell: bash
+        run: |
+          mapfile -t scripts < <(
+            git grep -Il '^#!/usr/bin/env -S uv run --script' -- '*.py' 'bin/*' || true
+          )
+          for script in "${scripts[@]}"; do
+            uv audit --script "$script"
+          done
+          (( ${#scripts[@]} )) || echo "No dependency-bearing Python scripts found"
+
+  python-security:
+    name: Python / security lint
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@c771a70e6277c0a99b617c7a806ffedaca235ff9 # v9.0.0
+        with:
+          version: "0.11.32"
+          python-version: "3.11"
+          enable-cache: false
+
+      - name: Scan Python scripts
+        shell: bash
+        run: |
+          mapfile -t python_files < <(
+            git ls-files -- 'bin/_common.py'
+            git grep -Il '^#!/usr/bin/env -S uv run --script' -- '*.py' 'bin/*' || true
+          )
+          if (( ${#python_files[@]} == 0 )); then
+            echo "No Python scripts found"
+            exit 0
+          fi
+          uvx bandit@1.9.4 --quiet --severity-level medium "${python_files[@]}"