diff --git a/.github/workflows/cd.yml b/.github/workflows/cd.yml
index ff28967..cde7e39 100644
--- a/.github/workflows/cd.yml
+++ b/.github/workflows/cd.yml
@@ -10,8 +10,26 @@ on:  # yamllint disable-line rule:truthy
       - main
 
 jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+      - name: Build site
+        run: |
+          docker run --rm \
+            -v "$PWD":/src \
+            -w /src \
+            hugomods/hugo:reg-0.147.9 hugo
+      - name: Validate pages
+        run: |
+          find content -name '*.md' \
+          -exec printf 'Checking %s\n' {} \; \
+          -exec ./validate-page.sh {} \;
   deploy:
     runs-on: ubuntu-latest
+    needs: validate
     steps:
       # Run Hugo on the server to build the site
       - name: Build Site with Hugo
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..01f46f7
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,24 @@
+---
+name: Validate Site
+
+on:
+  pull_request:
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+      - name: Build site
+        run: |
+          docker run --rm \
+            -v "$PWD":/src \
+            -w /src \
+            hugomods/hugo:reg-0.147.9 hugo
+      - name: Validate pages
+        run: |
+          find content -name '*.md' \
+          -exec printf 'Checking %s\n' {} \; \
+          -exec ./validate-page.sh {} \;
diff --git a/.yamllint.yml b/.yamllint.yml
index 412e2c4..b1b08b6 100644
--- a/.yamllint.yml
+++ b/.yamllint.yml
@@ -6,3 +6,4 @@ ignore: |
 
 rules:
   line-length: disable
+  truthy: disable
diff --git a/layouts/partials/head.html b/layouts/partials/head.html
index 1241f05..0de28fb 100644
--- a/layouts/partials/head.html
+++ b/layouts/partials/head.html
@@ -43,7 +43,7 @@
   <meta name="description" content="{{ . }}">
 {{- end }}
 {{- with .Site.Params.author.name }}
-  <meta name="author" content="{{ . }}"/>
+  <meta name="author" content="{{ . }}">
 {{- end }}
 {{- partial "seo/main.html" . }}
 {{- with .Site.Params.favicon }}
diff --git a/validate-page.sh b/validate-page.sh
index 195ae4e..ac9f898 100755
--- a/validate-page.sh
+++ b/validate-page.sh
@@ -12,8 +12,11 @@ path=$1
 # Collapse multiple slashes to 1
 path=$(echo "$path" | sed -E 's#/+#/#g')
 
+# Remove replace _index.md paths with the path that will lead to the index.
+if [[ $path == */_index.md ]]; then
+    path=${path%/_index.md}
 # Remove .md from paths.
-if [[ $path == *.md ]]; then
+elif [[ $path == *.md ]]; then
     path=${path%.md}
 fi