diff --git a/.github/workflows/autobump.yml b/.github/workflows/autobump.yml
index 6090e75..ddae227 100644
--- a/.github/workflows/autobump.yml
+++ b/.github/workflows/autobump.yml
@@ -74,8 +74,8 @@ jobs:
 
             bin/update-ruby-recipe "$latest" "$tarball_url" "$sha256"
             bin/validate-recipes
-            if ! git diff --quiet -- recipes/rubies.yml; then
-              git add recipes/rubies.yml
+            if ! git diff --quiet -- recipes/rubies.yml recipes/series.yml; then
+              git add recipes/rubies.yml recipes/series.yml
               git commit -m "Add Ruby ${latest}"
             fi
           done
@@ -121,8 +121,8 @@ jobs:
 
             bin/update-ruby-recipe "$version" "$tarball_url" "$sha256"
             bin/validate-recipes
-            if ! git diff --quiet -- recipes/rubies.yml; then
-              git add recipes/rubies.yml
+            if ! git diff --quiet -- recipes/rubies.yml recipes/series.yml; then
+              git add recipes/rubies.yml recipes/series.yml
               git commit -m "Add Ruby ${version}"
             fi
           done
@@ -134,3 +134,36 @@ jobs:
           else
             echo "No recipe changes to push"
           fi
+
+  notify-failure:
+    needs: autobump
+    if: ${{ failure() }}
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - name: Send failure email via Resend
+        env:
+          RESEND_API_KEY: ${{ secrets.RESEND_API_KEY }}
+          NOTIFY_EMAIL: ${{ secrets.NOTIFY_EMAIL }}
+          RUN_URL: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
+        run: |
+          set -euo pipefail
+          if [ -z "${RESEND_API_KEY:-}" ] || [ -z "${NOTIFY_EMAIL:-}" ]; then
+            echo "::warning::RESEND_API_KEY or NOTIFY_EMAIL is unset; skipping autobump failure notification"
+            exit 0
+          fi
+          payload=$(jq -n \
+            --arg to "$NOTIFY_EMAIL" \
+            --arg run_url "$RUN_URL" \
+            '{
+              from: "Ruby Releases <ruby@en.dev>",
+              to: [$to],
+              subject: "❌ Ruby autobump failed",
+              html: ("<p>The autobump workflow failed, so new Ruby releases are not being picked up.</p><p><a href=\"\($run_url | @html)\">View workflow run</a></p>")
+            }')
+          curl --fail-with-body -sS \
+            --retry 3 --retry-all-errors --retry-delay 2 --retry-max-time 60 \
+            -X POST 'https://api.resend.com/emails' \
+            -H "Authorization: Bearer ${RESEND_API_KEY}" \
+            -H 'Content-Type: application/json' \
+            -d "$payload"
diff --git a/libexec/update_ruby_recipe.rb b/libexec/update_ruby_recipe.rb
index 93f8337..45569f3 100755
--- a/libexec/update_ruby_recipe.rb
+++ b/libexec/update_ruby_recipe.rb
@@ -8,6 +8,7 @@ class UpdateRubyRecipeError < StandardError; end
 class UpdateRubyRecipe
   ROOT = File.expand_path("..", __dir__)
   RECIPE_PATH = File.join(ROOT, "recipes", "rubies.yml")
+  SERIES_PATH = File.join(ROOT, "recipes", "series.yml")
   PRE_RELEASE_RANK = {
     "preview" => 0,
     "rc" => 1
@@ -34,6 +35,7 @@ def run!
     rubies = doc.fetch("rubies")
     old = rubies[@version]
     entry = recipe_entry
+    register_series(entry.fetch("series"))
     if old == entry
       puts "Ruby #{@version} already exists in recipes/rubies.yml"
       return
@@ -46,6 +48,16 @@ def run!
 
   private
 
+  # A new minor series has no overrides yet, so it gets the defaults.
+  def register_series(name)
+    text = File.read(SERIES_PATH)
+    doc = YAML.safe_load(text, permitted_classes: [], aliases: false)
+    return if doc.fetch("series").key?(name)
+
+    File.write(SERIES_PATH, "#{text.chomp}\n  \"#{name}\": {}\n")
+    puts "Added series #{name} in recipes/series.yml"
+  end
+
   def recipe_entry
     entry = {
       "series" => @version[/\A\d+\.\d+/],