diff --git a/.github/workflows/api_doc.yml b/.github/workflows/api_doc.yml
index 245e8ba9e6e78..3a5897fb3f409 100644
--- a/.github/workflows/api_doc.yml
+++ b/.github/workflows/api_doc.yml
@@ -6,9 +6,6 @@ on:
   push:
     branches:
       - "**"
-  pull_request:
-    branches:
-      - "**"
 
 jobs:
   deploy:
diff --git a/.github/workflows/ci_archlinux.yml b/.github/workflows/ci_archlinux.yml
new file mode 100644
index 0000000000000..a1011e9e5b994
--- /dev/null
+++ b/.github/workflows/ci_archlinux.yml
@@ -0,0 +1,52 @@
+# https://help.github.com/en/articles/workflow-syntax-for-github-actions
+
+name: CI Arch Linux
+
+on:
+  push:
+    branches:
+      - "**"
+  schedule:
+    # Run every day at 02:00
+    - cron: "0 2 * * 0-6"
+
+jobs:
+  archlinux:
+    name: Arch Linux
+    runs-on: ubuntu-20.04
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [archlinux]
+        platform: [linux/amd64]
+        build_type: [Release]
+        codecov: [OFF]
+    env:
+      # Hosted on: https://hub.docker.com/repository/docker/dartsim/dart-dev
+      DART_DEV_IMAGE: dartsim/dart-dev
+      DOCKER_TAG: ${{ matrix.os }}-v7.0
+      PLATFORM: ${{ matrix.platform }}
+      COMPILER: gcc
+      BUILD_TYPE: ${{ matrix.build_type }}
+      BUILD_DARTPY: "${{ matrix.build_type == 'Debug' && 'OFF' || 'ON' }}"
+      CODECOV: ${{ matrix.codecov }}
+    steps:
+      # https://github.com/marketplace/actions/docker-setup-qemu
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Pull dev container
+        run: docker pull $DART_DEV_IMAGE:$DOCKER_TAG
+      - name: Build
+        run: |
+          if [ "$CODECOV" = "ON" ]; then
+            ci_env=`bash <(curl -s https://codecov.io/env)`
+          fi
+          docker run \
+            $ci_env -e CI=true \
+            --platform $PLATFORM \
+            --volume $GITHUB_WORKSPACE:$GITHUB_WORKSPACE \
+            --env-file ./.ci/docker/env.list \
+            $DART_DEV_IMAGE:$DOCKER_TAG \
+            /bin/sh -c "cd $GITHUB_WORKSPACE && ./.ci/build.sh"
diff --git a/.github/workflows/ci_macos.yml b/.github/workflows/ci_macos.yml
index bb1532ae73770..cd3c8aae2a6de 100644
--- a/.github/workflows/ci_macos.yml
+++ b/.github/workflows/ci_macos.yml
@@ -6,9 +6,6 @@ on:
   push:
     branches:
       - "**"
-  pull_request:
-    branches:
-      - "**"
   schedule:
     # Run every day at 02:00
     - cron: "0 2 * * 0-6"
diff --git a/.github/workflows/ci_ubuntu.yml b/.github/workflows/ci_ubuntu.yml
index 0b3d8718e9ba6..f004b4bc300cc 100644
--- a/.github/workflows/ci_ubuntu.yml
+++ b/.github/workflows/ci_ubuntu.yml
@@ -6,15 +6,11 @@ on:
   push:
     branches:
       - "**"
-  pull_request:
-    branches:
-      - "**"
   schedule:
     # Run every day at 02:00
     - cron: "0 2 * * 0-6"
 
 jobs:
-  # Linux distros on multiple architectures
   ubuntu:
     name: Ubuntu
     runs-on: ubuntu-20.04
@@ -45,7 +41,7 @@ jobs:
     env:
       # Hosted on: https://hub.docker.com/repository/docker/dartsim/dart-dev
       DART_DEV_IMAGE: dartsim/dart-dev
-      DOCKER_TAG: ${{ matrix.os }}-v6.10
+      DOCKER_TAG: ${{ matrix.os }}-v7.0
       PLATFORM: ${{ matrix.platform }}
       COMPILER: gcc
       BUILD_TYPE: ${{ matrix.build_type }}
diff --git a/.github/workflows/ci_windows.yml b/.github/workflows/ci_windows.yml
index b27f9f53e1abf..41858166b7070 100644
--- a/.github/workflows/ci_windows.yml
+++ b/.github/workflows/ci_windows.yml
@@ -6,9 +6,6 @@ on:
   push:
     branches:
       - "**"
-  pull_request:
-    branches:
-      - "**"
   schedule:
     # Run every day at 02:00
     - cron: "0 2 * * 0-6"
diff --git a/README.md b/README.md
index 1d3fffa94ab5b..87d6e7f24e3f6 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
 
 | Item              | Status                                                                                                                                 |
 | ----------------- | -------------------------------------------------------------------------------------------------------------------------------------- |
-| Build Status      | [![CI Ubuntu](https://github.com/dartsim/dart/actions/workflows/ci_ubuntu.yml/badge.svg)](https://github.com/dartsim/dart/actions/workflows/ci_ubuntu.yml) [![CI macOS](https://github.com/dartsim/dart/actions/workflows/ci_macos.yml/badge.svg)](https://github.com/dartsim/dart/actions/workflows/ci_macos.yml) [![CI Windows](https://github.com/dartsim/dart/actions/workflows/ci_windows.yml/badge.svg)](https://github.com/dartsim/dart/actions/workflows/ci_windows.yml) |
+| Build Status      | [![CI Ubuntu](https://github.com/dartsim/dart/actions/workflows/ci_ubuntu.yml/badge.svg)](https://github.com/dartsim/dart/actions/workflows/ci_ubuntu.yml) [![CI Arch Linux](https://github.com/dartsim/dart/actions/workflows/ci_archlinux.yml/badge.svg)](https://github.com/dartsim/dart/actions/workflows/ci_archlinux.yml) [![CI macOS](https://github.com/dartsim/dart/actions/workflows/ci_macos.yml/badge.svg)](https://github.com/dartsim/dart/actions/workflows/ci_macos.yml) [![CI Windows](https://github.com/dartsim/dart/actions/workflows/ci_windows.yml/badge.svg)](https://github.com/dartsim/dart/actions/workflows/ci_windows.yml) |
 | API Documentation | [![API Documentation](https://github.com/dartsim/dart/actions/workflows/api_doc.yml/badge.svg)](https://github.com/dartsim/dart/actions/workflows/api_doc.yml) |
 | Coverage          | [![codecov](https://codecov.io/gh/dartsim/dart/branch/main/graph/badge.svg)](https://codecov.io/gh/dartsim/dart) |
 | Static Analysis   | [![Codacy Badge](https://app.codacy.com/project/badge/Grade/2d95a9b951be4b73a71097670ec351e8)](https://www.codacy.com/gh/dartsim/dart/dashboard?utm_source=github.com&amp;utm_medium=referral&amp;utm_content=dartsim/dart&amp;utm_campaign=Badge_Grade) |
diff --git a/dart/dynamics/detail/DegreeOfFreedomPtr.hpp b/dart/dynamics/detail/DegreeOfFreedomPtr.hpp
index a2d453a1c05a9..23ee64fdd8464 100644
--- a/dart/dynamics/detail/DegreeOfFreedomPtr.hpp
+++ b/dart/dynamics/detail/DegreeOfFreedomPtr.hpp
@@ -218,7 +218,7 @@ class TemplateDegreeOfFreedomPtr
   TemplateBodyNodePtr<BodyNodeT> mBodyNodePtr;
 
   /// Local index of this DegreeOfFreedom within its Joint
-  std::size_t mIndex;
+  std::size_t mIndex = 0;
 };
 
 /// TemplateWeakDegreeOfFreedomPtr is a templated class that enables users to
@@ -331,7 +331,7 @@ class TemplateWeakDegreeOfFreedomPtr
   TemplateWeakBodyNodePtr<BodyNodeT> mWeakBodyNode;
 
   /// Local index of this DegreeOfFreedom within its Joint
-  std::size_t mIndex;
+  std::size_t mIndex = 0;
 };
 
 } // namespace dynamics