diff --git a/.gitignore b/.gitignore
index 6031947e..e0fa8aa3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -26,7 +26,8 @@ yarn-debug.log*
 /config/puma.rb
 
 # Ignore public uploaded files
-public/uploads
+public/uploads/
+public/sitemaps/
 
 # Ignore public/assets as assets are generated in each server when deploying
 public/assets
@@ -41,9 +42,10 @@ public/sw.js
 spec/decidim_dummy_app/
 .rspec-failures
 
-# Ignore idea config files
+# Ignore IDE config files
 .idea
 *.iml
+.vscode/
 
 coverage/
 storage/
diff --git a/Gemfile b/Gemfile
index 5d146952..79e6ed57 100644
--- a/Gemfile
+++ b/Gemfile
@@ -36,6 +36,7 @@ gem "daemons"
 gem "deface"
 gem "delayed_job_active_record"
 
+gem "sitemap_generator", "~> 7.0"
 gem "whenever", require: false
 
 gem "recaptcha"
diff --git a/Gemfile.lock b/Gemfile.lock
index ca03c27e..1ce70633 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -860,6 +860,8 @@ GEM
       simplecov (~> 0.19)
     simplecov-html (0.13.2)
     simplecov_json_formatter (0.1.4)
+    sitemap_generator (7.0.1)
+      builder (~> 3.0)
     smart_properties (1.17.0)
     snaky_hash (2.0.3)
       hashie (>= 0.1.0, < 6)
@@ -974,6 +976,7 @@ DEPENDENCIES
   rubocop-faker
   rubocop-rspec
   rubocop-rspec_rails
+  sitemap_generator (~> 7.0)
   soda-ruby
   stringio (~> 3.1.7)
   web-console
diff --git a/config/schedule.rb b/config/schedule.rb
index 1041b3e9..81ae3317 100644
--- a/config/schedule.rb
+++ b/config/schedule.rb
@@ -22,6 +22,10 @@
   rake "tmp:clear"
 end
 
+every 1.day, at: "3:15 am" do
+  rake "sitemap:generate"
+end
+
 every 5.minutes do
   rake "participatory_processes_phases:enqueue_change_active_step"
 end
diff --git a/config/sitemap.rb b/config/sitemap.rb
new file mode 100644
index 00000000..5b30e9c0
--- /dev/null
+++ b/config/sitemap.rb
@@ -0,0 +1,241 @@
+# frozen_string_literal: true
+
+# ---------------------------------------------------------------------------
+# Sitemap configuration for participa.gencat.cat
+#
+# Groups and their content:
+#   processes      – participatory process landing pages + component pages
+#   regulations    – /regulations index + regulation process + component pages
+#   assemblies     – assembly landing pages + component pages
+#   meetings       – individual meeting show pages (all spaces)
+#   proposals      – individual proposal show pages (all spaces)
+#   pages          – homepage, listing pages, static CMS pages
+#   blogs          – individual blog post show pages (all spaces)
+#   debates        – individual debate show pages (all spaces)
+#   budgets        – individual budget project show pages (all spaces)
+#   accountability – individual accountability result show pages (all spaces)
+#   attachments    – PDF and image file blob URLs
+#
+# Generated files land in public/sitemaps/.
+# The master index is public/sitemaps/sitemap.xml.gz.
+# ---------------------------------------------------------------------------
+
+# Make Rails route helpers (incl. rails_blob_path) available inside the
+# create block and all group blocks.
+SitemapGenerator::Interpreter.send(:include, Rails.application.routes.url_helpers)
+
+# Helper: returns the URL prefix for a participatory space, or nil for
+# space types that are not publicly routable.
+SitemapGenerator::Interpreter.class_eval do
+  def space_url_prefix(space)
+    if space.is_a?(Decidim::ParticipatoryProcess)
+      "/processes"
+    elsif space.is_a?(Decidim::Assembly)
+      "/assemblies"
+    end
+  end
+end
+
+organization = Decidim::Organization.first
+host = "https://#{organization.host}"
+regulation_group_id = Rails.application.config.regulation
+
+SitemapGenerator::Sitemap.default_host = host
+SitemapGenerator::Sitemap.sitemaps_path = "sitemaps/"
+SitemapGenerator::Sitemap.create_index = true
+SitemapGenerator::Sitemap.compress = true
+SitemapGenerator::Sitemap.include_root = false
+SitemapGenerator::Sitemap.include_index = false
+
+SitemapGenerator::Sitemap.create do
+  # ── Participatory Processes (excluding regulations) ────────────────────────
+  group(filename: :processes) do
+    Decidim::ParticipatoryProcess
+      .where(organization:)
+      .published
+      .where("decidim_participatory_process_group_id IS NULL OR decidim_participatory_process_group_id != ?", regulation_group_id)
+      .preload(:components)
+      .find_each do |process|
+        next if process.slug.blank?
+
+        add "/processes/#{process.slug}",
+            lastmod: process.updated_at, changefreq: "weekly", priority: 0.8
+
+        process.components.select { |c| c.published_at.present? }.each do |component|
+          add "/processes/#{process.slug}/f/#{component.id}",
+              lastmod: component.updated_at, changefreq: "weekly", priority: 0.6
+        end
+      end
+  end
+
+  # ── Regulations ─────────────────────────────────────────────────────────────
+  group(filename: :regulations) do
+    add "/regulations", changefreq: "weekly", priority: 0.7
+
+    Decidim::ParticipatoryProcess
+      .where(organization:, decidim_participatory_process_group_id: regulation_group_id)
+      .published
+      .preload(:components)
+      .find_each do |process|
+        next if process.slug.blank?
+
+        add "/processes/#{process.slug}",
+            lastmod: process.updated_at, changefreq: "monthly", priority: 0.7
+
+        process.components.select { |c| c.published_at.present? }.each do |component|
+          add "/processes/#{process.slug}/f/#{component.id}",
+              lastmod: component.updated_at, changefreq: "monthly", priority: 0.5
+        end
+      end
+  end
+
+  # ── Assemblies ──────────────────────────────────────────────────────────────
+  group(filename: :assemblies) do
+    Decidim::Assembly
+      .where(organization:)
+      .published
+      .preload(:components)
+      .find_each do |assembly|
+        next if assembly.slug.blank?
+
+        add "/assemblies/#{assembly.slug}",
+            lastmod: assembly.updated_at, changefreq: "weekly", priority: 0.8
+
+        assembly.components.select { |c| c.published_at.present? }.each do |component|
+          add "/assemblies/#{assembly.slug}/f/#{component.id}",
+              lastmod: component.updated_at, changefreq: "weekly", priority: 0.6
+        end
+      end
+  end
+
+  # ── Meetings ────────────────────────────────────────────────────────────────
+  group(filename: :meetings) do
+    Decidim::Meetings::Meeting
+      .joins(:component)
+      .where.not(decidim_components: { published_at: nil })
+      .where.not(published_at: nil)
+      .preload(component: :participatory_space)
+      .find_each do |meeting|
+        space = meeting.component.participatory_space
+        prefix = space_url_prefix(space)
+        next unless prefix && space&.slug.present?
+
+        add "#{prefix}/#{space.slug}/f/#{meeting.decidim_component_id}/meetings/#{meeting.id}",
+            lastmod: meeting.updated_at, changefreq: "weekly", priority: 0.5
+      end
+  end
+
+  # ── Proposals ───────────────────────────────────────────────────────────────
+  group(filename: :proposals) do
+    Decidim::Proposals::Proposal
+      .joins(:component)
+      .where.not(decidim_components: { published_at: nil })
+      .where.not(published_at: nil)
+      .preload(component: :participatory_space)
+      .find_each do |proposal|
+        space = proposal.component.participatory_space
+        prefix = space_url_prefix(space)
+        next unless prefix && space&.slug.present?
+
+        add "#{prefix}/#{space.slug}/f/#{proposal.decidim_component_id}/proposals/#{proposal.id}",
+            lastmod: proposal.updated_at, changefreq: "monthly", priority: 0.5
+      end
+  end
+
+  # ── Static Pages ────────────────────────────────────────────────────────────
+  group(filename: :pages) do
+    add "/", changefreq: "daily", priority: 1.0
+    add "/processes", changefreq: "daily", priority: 0.7
+    add "/assemblies", changefreq: "daily", priority: 0.7
+
+    Decidim::StaticPage
+      .where(organization:)
+      .find_each do |page|
+        add "/pages/#{page.slug}",
+            lastmod: page.updated_at, changefreq: "monthly", priority: 0.4
+      end
+  end
+
+  # ── Blog Posts ──────────────────────────────────────────────────────────────
+  group(filename: :blogs) do
+    Decidim::Blogs::Post
+      .joins(:component)
+      .where.not(decidim_components: { published_at: nil })
+      .preload(component: :participatory_space)
+      .find_each do |post|
+        space = post.component.participatory_space
+        prefix = space_url_prefix(space)
+        next unless prefix && space&.slug.present?
+
+        add "#{prefix}/#{space.slug}/f/#{post.decidim_component_id}/posts/#{post.id}",
+            lastmod: post.updated_at, changefreq: "monthly", priority: 0.5
+      end
+  end
+
+  # ── Debates ─────────────────────────────────────────────────────────────────
+  group(filename: :debates) do
+    Decidim::Debates::Debate
+      .joins(:component)
+      .where.not(decidim_components: { published_at: nil })
+      .preload(component: :participatory_space)
+      .find_each do |debate|
+        space = debate.component.participatory_space
+        prefix = space_url_prefix(space)
+        next unless prefix && space&.slug.present?
+
+        add "#{prefix}/#{space.slug}/f/#{debate.decidim_component_id}/debates/#{debate.id}",
+            lastmod: debate.updated_at, changefreq: "weekly", priority: 0.5
+      end
+  end
+
+  # ── Budget Projects ─────────────────────────────────────────────────────────
+  group(filename: :budgets) do
+    Decidim::Budgets::Project
+      .joins(budget: :component)
+      .where.not(decidim_components: { published_at: nil })
+      .preload(budget: { component: :participatory_space })
+      .find_each do |project|
+        space = project.budget.component.participatory_space
+        prefix = space_url_prefix(space)
+        next unless prefix && space&.slug.present?
+
+        add "#{prefix}/#{space.slug}/f/#{project.budget.decidim_component_id}" \
+            "/budgets/#{project.decidim_budgets_budget_id}/projects/#{project.id}",
+            lastmod: project.updated_at, changefreq: "monthly", priority: 0.4
+      end
+  end
+
+  # ── Accountability Results ───────────────────────────────────────────────────
+  group(filename: :accountability) do
+    Decidim::Accountability::Result
+      .joins(:component)
+      .where.not(decidim_components: { published_at: nil })
+      .preload(component: :participatory_space)
+      .find_each do |result|
+        space = result.component.participatory_space
+        prefix = space_url_prefix(space)
+        next unless prefix && space&.slug.present?
+
+        add "#{prefix}/#{space.slug}/f/#{result.decidim_component_id}/results/#{result.id}",
+            lastmod: result.updated_at, changefreq: "monthly", priority: 0.4
+      end
+  end
+
+  # ── Attachments (PDFs and images) ───────────────────────────────────────────
+  # Adds blob redirect URLs so search engines can index uploaded documents and
+  # images.  The ActiveStorage redirect path is stable (the signed_id does not
+  # expire).
+  group(filename: :attachments) do
+    Decidim::Attachment
+      .where("content_type LIKE 'image/%' OR content_type = 'application/pdf'")
+      .find_each do |attachment|
+        next unless attachment.file.attached?
+
+        blob_path = rails_blob_path(attachment.file, only_path: true)
+
+        add blob_path,
+            changefreq: "yearly",
+            priority: attachment.content_type == "application/pdf" ? 0.4 : 0.3
+      end
+  end
+end
diff --git a/lib/tasks/sitemap.rake b/lib/tasks/sitemap.rake
new file mode 100644
index 00000000..17d7f98d
--- /dev/null
+++ b/lib/tasks/sitemap.rake
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+namespace :sitemap do
+  desc "Generate sitemaps, purge stale files, and update robots.txt"
+  task generate: :environment do
+    unless Rails.env.production?
+      puts "Sitemap generation is intended for production environments only. Aborting."
+      exit(-1)
+    end
+
+    sitemaps_dir = Rails.public_path.join("sitemaps")
+
+    # ── Step 1: Generate ────────────────────────────────────────────────────
+    generation_started_at = Time.current
+
+    SitemapGenerator::Sitemap.verbose = true
+    load Rails.root.join("config", "sitemap.rb")
+
+    # ── Step 2: Purge stale files ────────────────────────────────────────────
+    # Any sitemap file whose mtime predates this run was produced by a previous
+    # generation and is no longer valid (e.g. a group that produced N numbered
+    # files before now only produces N-1).
+    stale = Dir.glob(sitemaps_dir.join("*.xml.gz")).select do |file|
+      File.mtime(file) < generation_started_at
+    end
+
+    stale.each do |file|
+      File.delete(file)
+      puts "Removed stale sitemap: #{File.basename(file)}"
+    end
+
+    # ── Step 3: Rebuild robots.txt ───────────────────────────────────────────
+    organization = Decidim::Organization.first
+    host = "https://#{organization.host}"
+
+    new_sitemap_files = Dir.glob(sitemaps_dir.join("*.xml.gz"))
+    sitemap_directives = new_sitemap_files.map do |file|
+      "Sitemap: #{host}/sitemaps/#{File.basename(file)}"
+    end
+
+    robots_path = Rails.public_path.join("robots.txt")
+    current_content = File.read(robots_path)
+
+    # Strip any existing Sitemap: lines (including the trailing newline of each)
+    cleaned_content = current_content.gsub(/^Sitemap:.*\n?/, "").rstrip
+
+    new_content = "#{cleaned_content}\n\n#{sitemap_directives.join("\n")}\n"
+    File.write(robots_path, new_content)
+
+    puts "robots.txt updated with #{sitemap_directives.size} Sitemap directives."
+  end
+end
diff --git a/spec/factories.rb b/spec/factories.rb
index fea89b12..ce0ba5a2 100644
--- a/spec/factories.rb
+++ b/spec/factories.rb
@@ -4,6 +4,11 @@
 require "decidim/participatory_processes/test/factories"
 require "decidim/proposals/test/factories"
 require "decidim/meetings/test/factories"
+require "decidim/assemblies/test/factories"
+require "decidim/blogs/test/factories"
+require "decidim/debates/test/factories"
+require "decidim/budgets/test/factories"
+require "decidim/accountability/test/factories"
 
 FactoryBot.define do
   factory :external_author, class: "Decidim::ExternalAuthor" do
diff --git a/spec/lib/sitemap_spec.rb b/spec/lib/sitemap_spec.rb
new file mode 100644
index 00000000..28a5a8c6
--- /dev/null
+++ b/spec/lib/sitemap_spec.rb
@@ -0,0 +1,368 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+require "zlib"
+require "uri"
+
+describe "config/sitemap.rb" do
+  let!(:organization) { create(:organization) }
+  let(:tmpdir) { Pathname.new(Dir.mktmpdir) }
+
+  # Save and restore SitemapGenerator state around each example so that the
+  # global singleton does not leak settings between tests.
+  around do |example|
+    orig_public_path = SitemapGenerator::Sitemap.public_path
+    orig_verbose = SitemapGenerator::Sitemap.verbose
+
+    FileUtils.mkdir_p(tmpdir.join("sitemaps"))
+    SitemapGenerator::Sitemap.public_path = tmpdir
+    SitemapGenerator::Sitemap.verbose = false
+
+    example.run
+  ensure
+    FileUtils.rm_rf(tmpdir)
+    SitemapGenerator::Sitemap.public_path = orig_public_path
+    SitemapGenerator::Sitemap.verbose = orig_verbose
+  end
+
+  # Loads config/sitemap.rb, which sets options on SitemapGenerator::Sitemap
+  # and immediately runs SitemapGenerator::Sitemap.create, writing .xml.gz
+  # files to tmpdir/sitemaps/.
+  def generate_sitemap!
+    load Rails.root.join("config", "sitemap.rb")
+  end
+
+  # Returns the path portion of every URL found across all non-index sitemap
+  # files produced by the last generate_sitemap! call.
+  def sitemap_paths
+    Dir.glob(tmpdir.join("sitemaps", "*.xml.gz"))
+       .reject { |f| File.basename(f) == "sitemap.xml.gz" }
+       .flat_map do |path|
+         xml = Zlib::GzipReader.open(path, &:read)
+         Nokogiri::XML(xml)
+                 .xpath("//sm:loc", "sm" => "http://www.sitemaps.org/schemas/sitemap/0.9")
+                 .map { |node| URI.parse(node.text).path }
+       end
+  end
+
+  # Returns the path portion of every URL found in a specific named sub-sitemap.
+  # filename should be a Symbol or String matching the group filename (e.g. :processes).
+  def sitemap_paths_for(filename)
+    path = tmpdir.join("sitemaps", "#{filename}.xml.gz")
+    return [] unless File.exist?(path)
+
+    xml = Zlib::GzipReader.open(path, &:read)
+    Nokogiri::XML(xml)
+            .xpath("//sm:loc", "sm" => "http://www.sitemaps.org/schemas/sitemap/0.9")
+            .map { |node| URI.parse(node.text).path }
+  end
+
+  # ── Participatory Processes ──────────────────────────────────────────────────
+
+  describe "processes group" do
+    let!(:process) { create(:participatory_process, :published, :with_steps, organization:) }
+    let!(:published_component) { create(:component, :published, participatory_space: process) }
+    let!(:unpublished_component) { create(:component, :unpublished, participatory_space: process) }
+    let!(:unpublished_process) { create(:participatory_process, organization:, published_at: nil) }
+    let!(:regulation_process) do
+      create(:participatory_process, :published, :with_steps, organization:,
+                                                              decidim_participatory_process_group_id: Rails.application.config.regulation)
+    end
+
+    before { generate_sitemap! }
+
+    it "includes the published process landing page" do
+      expect(sitemap_paths).to include("/processes/#{process.slug}")
+    end
+
+    it "includes published component pages for the process" do
+      expect(sitemap_paths).to include("/processes/#{process.slug}/f/#{published_component.id}")
+    end
+
+    it "excludes unpublished component pages" do
+      expect(sitemap_paths).not_to include("/processes/#{process.slug}/f/#{unpublished_component.id}")
+    end
+
+    it "excludes unpublished processes" do
+      expect(sitemap_paths).not_to include("/processes/#{unpublished_process.slug}")
+    end
+
+    it "excludes regulation processes from the processes group" do
+      expect(sitemap_paths_for(:processes)).not_to include("/processes/#{regulation_process.slug}")
+    end
+  end
+
+  # ── Regulations ──────────────────────────────────────────────────────────────
+
+  describe "regulations group" do
+    let!(:regulation_process) do
+      create(:participatory_process, :published, :with_steps, organization:,
+                                                              decidim_participatory_process_group_id: Rails.application.config.regulation)
+    end
+    let!(:regulation_component) do
+      create(:component, :published, participatory_space: regulation_process)
+    end
+
+    before { generate_sitemap! }
+
+    it "includes the /regulations listing page" do
+      expect(sitemap_paths).to include("/regulations")
+    end
+
+    it "includes the regulation process page" do
+      expect(sitemap_paths).to include("/processes/#{regulation_process.slug}")
+    end
+
+    it "includes the regulation process component page" do
+      expect(sitemap_paths).to include("/processes/#{regulation_process.slug}/f/#{regulation_component.id}")
+    end
+  end
+
+  # ── Assemblies ───────────────────────────────────────────────────────────────
+
+  describe "assemblies group" do
+    let!(:assembly) { create(:assembly, :published, organization:) }
+    let!(:published_component) { create(:component, :published, participatory_space: assembly) }
+    let!(:unpublished_assembly) { create(:assembly, :unpublished, organization:) }
+
+    before { generate_sitemap! }
+
+    it "includes the published assembly landing page" do
+      expect(sitemap_paths).to include("/assemblies/#{assembly.slug}")
+    end
+
+    it "includes published component pages for the assembly" do
+      expect(sitemap_paths).to include("/assemblies/#{assembly.slug}/f/#{published_component.id}")
+    end
+
+    it "excludes unpublished assemblies" do
+      expect(sitemap_paths).not_to include("/assemblies/#{unpublished_assembly.slug}")
+    end
+  end
+
+  # ── Meetings ─────────────────────────────────────────────────────────────────
+
+  describe "meetings group" do
+    let!(:process) { create(:participatory_process, :published, :with_steps, organization:) }
+    let!(:meetings_component) { create(:meeting_component, :published, participatory_space: process) }
+    let!(:meeting) { create(:meeting, :published, component: meetings_component) }
+    let!(:unpublished_meetings_component) do
+      create(:meeting_component, :unpublished, participatory_space: process)
+    end
+    let!(:meeting_in_unpublished_component) do
+      create(:meeting, :published, component: unpublished_meetings_component)
+    end
+
+    before { generate_sitemap! }
+
+    it "includes meetings from published components" do
+      expect(sitemap_paths).to include(
+        "/processes/#{process.slug}/f/#{meetings_component.id}/meetings/#{meeting.id}"
+      )
+    end
+
+    it "excludes meetings from unpublished components" do
+      expect(sitemap_paths).not_to include(
+        "/processes/#{process.slug}/f/#{unpublished_meetings_component.id}/meetings/#{meeting_in_unpublished_component.id}"
+      )
+    end
+  end
+
+  # ── Proposals ────────────────────────────────────────────────────────────────
+
+  describe "proposals group" do
+    let!(:process) { create(:participatory_process, :published, :with_steps, organization:) }
+    let!(:proposals_component) { create(:proposal_component, :published, participatory_space: process) }
+    let!(:proposal) { create(:proposal, :published, component: proposals_component) }
+    let!(:draft_proposal) { create(:proposal, :draft, component: proposals_component) }
+
+    before { generate_sitemap! }
+
+    it "includes published proposals" do
+      expect(sitemap_paths).to include(
+        "/processes/#{process.slug}/f/#{proposals_component.id}/proposals/#{proposal.id}"
+      )
+    end
+
+    it "excludes draft (unpublished) proposals" do
+      expect(sitemap_paths).not_to include(
+        "/processes/#{process.slug}/f/#{proposals_component.id}/proposals/#{draft_proposal.id}"
+      )
+    end
+  end
+
+  # ── Static Pages ─────────────────────────────────────────────────────────────
+
+  describe "pages group" do
+    let!(:static_page) { create(:static_page, organization:) }
+
+    before { generate_sitemap! }
+
+    it "includes the root URL" do
+      # SitemapGenerator normalises the root to the bare host (no trailing slash),
+      # so URI.parse gives path "".  Accept both forms to be safe.
+      expect(sitemap_paths & ["", "/"]).not_to be_empty
+    end
+
+    it "includes the processes listing" do
+      expect(sitemap_paths).to include("/processes")
+    end
+
+    it "includes the assemblies listing" do
+      expect(sitemap_paths).to include("/assemblies")
+    end
+
+    it "includes static CMS pages" do
+      expect(sitemap_paths).to include("/pages/#{static_page.slug}")
+    end
+  end
+
+  # ── Blog Posts ───────────────────────────────────────────────────────────────
+
+  describe "blogs group" do
+    let!(:process) { create(:participatory_process, :published, :with_steps, organization:) }
+    let!(:post_component) { create(:post_component, :published, participatory_space: process) }
+    let!(:post) { create(:post, component: post_component) }
+
+    before { generate_sitemap! }
+
+    it "includes published blog posts" do
+      expect(sitemap_paths).to include(
+        "/processes/#{process.slug}/f/#{post_component.id}/posts/#{post.id}"
+      )
+    end
+  end
+
+  # ── Debates ──────────────────────────────────────────────────────────────────
+
+  describe "debates group" do
+    let!(:process) { create(:participatory_process, :published, :with_steps, organization:) }
+    let!(:debates_component) { create(:debates_component, :published, participatory_space: process) }
+    let!(:debate) { create(:debate, component: debates_component) }
+
+    before { generate_sitemap! }
+
+    it "includes debates from published components" do
+      expect(sitemap_paths).to include(
+        "/processes/#{process.slug}/f/#{debates_component.id}/debates/#{debate.id}"
+      )
+    end
+  end
+
+  # ── Budget Projects ───────────────────────────────────────────────────────────
+
+  describe "budgets group" do
+    let!(:process) { create(:participatory_process, :published, :with_steps, organization:) }
+    let!(:budgets_component) { create(:budgets_component, :published, participatory_space: process) }
+    let!(:budget) { create(:budget, component: budgets_component) }
+    let!(:project) { create(:project, budget:) }
+
+    before { generate_sitemap! }
+
+    it "includes budget projects from published components" do
+      expect(sitemap_paths).to include(
+        "/processes/#{process.slug}/f/#{budgets_component.id}/budgets/#{budget.id}/projects/#{project.id}"
+      )
+    end
+  end
+
+  # ── Accountability Results ────────────────────────────────────────────────────
+
+  describe "accountability group" do
+    let!(:process) { create(:participatory_process, :published, :with_steps, organization:) }
+    let!(:accountability_component) do
+      create(:accountability_component, :published, participatory_space: process)
+    end
+    let!(:result) { create(:result, component: accountability_component) }
+
+    before { generate_sitemap! }
+
+    it "includes accountability results from published components" do
+      expect(sitemap_paths).to include(
+        "/processes/#{process.slug}/f/#{accountability_component.id}/results/#{result.id}"
+      )
+    end
+  end
+
+  # ── Attachments ───────────────────────────────────────────────────────────────
+
+  describe "attachments group" do
+    let!(:process) { create(:participatory_process, :published, :with_steps, organization:) }
+
+    context "with an image attachment" do
+      let!(:attachment) do
+        create(:attachment, attached_to: process, content_type: "image/jpeg")
+      end
+
+      before { generate_sitemap! }
+
+      it "includes the ActiveStorage blob path for the image" do
+        blob_path = Rails.application.routes.url_helpers.rails_blob_path(attachment.file, only_path: true)
+        expect(sitemap_paths).to include(blob_path)
+      end
+    end
+
+    context "with a PDF attachment" do
+      let!(:attachment) do
+        create(:attachment, attached_to: process,
+                            content_type: "application/pdf",
+                            file: Decidim::Dev.test_file("Exampledocument.pdf", "application/pdf"))
+      end
+
+      before { generate_sitemap! }
+
+      it "includes the ActiveStorage blob path for the PDF" do
+        blob_path = Rails.application.routes.url_helpers.rails_blob_path(attachment.file, only_path: true)
+        expect(sitemap_paths).to include(blob_path)
+      end
+    end
+
+    context "with a plain-text attachment" do
+      let!(:other_attachment) do
+        # Create an attachment with a non-image, non-PDF content type by directly
+        # updating the column after creation (factory always creates images).
+        att = create(:attachment, attached_to: process)
+        att.update_column(:content_type, "text/plain") # rubocop:disable Rails/SkipsModelValidations
+        att
+      end
+
+      before { generate_sitemap! }
+
+      it "excludes non-image, non-PDF attachments" do
+        blob_path = Rails.application.routes.url_helpers.rails_blob_path(other_attachment.file, only_path: true)
+        expect(sitemap_paths).not_to include(blob_path)
+      end
+    end
+  end
+
+  # ── Sitemap index ─────────────────────────────────────────────────────────────
+
+  describe "sitemap index" do
+    before { generate_sitemap! }
+
+    it "creates a sitemap index file" do
+      expect(File.exist?(tmpdir.join("sitemaps", "sitemap.xml.gz"))).to be true
+    end
+
+    it "creates at least one sub-sitemap per content group" do
+      sub_sitemaps = Dir.glob(tmpdir.join("sitemaps", "*.xml.gz"))
+                        .reject { |f| File.basename(f) == "sitemap.xml.gz" }
+      expect(sub_sitemaps.count).to be >= 1
+    end
+
+    it "index references all generated sub-sitemap files" do
+      sub_sitemaps = Dir.glob(tmpdir.join("sitemaps", "*.xml.gz"))
+                        .reject { |f| File.basename(f) == "sitemap.xml.gz" }
+                        .map { |f| File.basename(f) }
+
+      index_xml = Zlib::GzipReader.open(tmpdir.join("sitemaps", "sitemap.xml.gz"), &:read)
+      index_locs = Nokogiri::XML(index_xml)
+                           .xpath("//sm:loc", "sm" => "http://www.sitemaps.org/schemas/sitemap/0.9")
+                           .map { |node| File.basename(node.text) }
+
+      sub_sitemaps.each do |filename|
+        expect(index_locs).to include(filename)
+      end
+    end
+  end
+end
diff --git a/spec/lib/tasks/sitemap_rake_spec.rb b/spec/lib/tasks/sitemap_rake_spec.rb
new file mode 100644
index 00000000..3a0d2df4
--- /dev/null
+++ b/spec/lib/tasks/sitemap_rake_spec.rb
@@ -0,0 +1,125 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe "sitemap:generate rake task" do
+  subject(:task) { Rake::Task["sitemap:generate"] }
+
+  before do
+    Rails.application.load_tasks unless Rake::Task.task_defined?("sitemap:generate")
+    task.reenable
+  end
+
+  # ── Production guard ────────────────────────────────────────────────────────
+
+  describe "production guard" do
+    before { allow(Rails.env).to receive(:production?).and_return(false) }
+
+    it "exits when not running in production" do
+      expect { task.invoke }.to raise_error(SystemExit)
+    end
+  end
+
+  # ── Production behaviour ────────────────────────────────────────────────────
+
+  context "when running in production" do
+    let!(:organization) { create(:organization) }
+    let(:tmpdir) { Pathname.new(Dir.mktmpdir) }
+
+    # rspec-mocks stubs must be set up in before/it/after, not in around.
+    before do
+      allow(Rails.env).to receive(:production?).and_return(true)
+      allow(Rails).to receive(:public_path).and_return(tmpdir)
+    end
+
+    # File-system isolation and SitemapGenerator state go in around so that
+    # cleanup runs even when an example raises.
+    around do |example|
+      orig_public_path = SitemapGenerator::Sitemap.public_path
+      orig_verbose = SitemapGenerator::Sitemap.verbose
+
+      FileUtils.mkdir_p(tmpdir.join("sitemaps"))
+      File.write(tmpdir.join("robots.txt"), initial_robots_txt)
+
+      SitemapGenerator::Sitemap.public_path = tmpdir
+      SitemapGenerator::Sitemap.verbose = false
+
+      example.run
+    ensure
+      FileUtils.rm_rf(tmpdir)
+      SitemapGenerator::Sitemap.public_path = orig_public_path
+      SitemapGenerator::Sitemap.verbose = orig_verbose
+    end
+
+    let(:initial_robots_txt) do
+      <<~ROBOTS
+        # See http://www.robotstxt.org/robotstxt.html
+
+        User-agent: *
+        Disallow: /admin/
+        Allow: /processes/
+        Sitemap: https://participa.gencat.cat/sitemaps/old_sitemap.xml.gz
+      ROBOTS
+    end
+
+    # ── Stale file purge ──────────────────────────────────────────────────────
+
+    describe "stale file cleanup" do
+      let(:stale_path) { tmpdir.join("sitemaps", "stale_processes.xml.gz") }
+
+      before do
+        # Create a file that predates the generation run.
+        # File.utime requires Integer/Float timestamps in Ruby 3.1+.
+        FileUtils.touch(stale_path)
+        File.utime(1.hour.ago.to_i, 1.hour.ago.to_i, stale_path)
+      end
+
+      it "removes sitemap files that predate the current generation run" do
+        task.invoke
+        expect(File.exist?(stale_path)).to be false
+      end
+
+      it "keeps sitemap files that were written during the current generation run" do
+        task.invoke
+        fresh_files = Dir.glob(tmpdir.join("sitemaps", "*.xml.gz"))
+        expect(fresh_files).not_to be_empty
+      end
+    end
+
+    # ── robots.txt update ─────────────────────────────────────────────────────
+
+    describe "robots.txt update" do
+      before { task.invoke }
+
+      let(:robots_content) { File.read(tmpdir.join("robots.txt")) }
+
+      it "removes stale Sitemap: lines from the previous run" do
+        expect(robots_content).not_to include("old_sitemap.xml.gz")
+      end
+
+      it "adds a Sitemap: directive for every generated file" do
+        generated = Dir.glob(tmpdir.join("sitemaps", "*.xml.gz")).map { |f| File.basename(f) }
+        expect(generated).not_to be_empty
+
+        generated.each do |filename|
+          expect(robots_content).to include("Sitemap: https://#{organization.host}/sitemaps/#{filename}")
+        end
+      end
+
+      it "preserves User-agent rules" do
+        expect(robots_content).to include("User-agent: *")
+        expect(robots_content).to include("Disallow: /admin/")
+        expect(robots_content).to include("Allow: /processes/")
+      end
+
+      it "does not duplicate Sitemap: entries when run multiple times" do
+        task.reenable
+        task.invoke
+
+        sitemap_lines = File.readlines(tmpdir.join("robots.txt"))
+                            .select { |l| l.start_with?("Sitemap:") }
+        expect(sitemap_lines.uniq).to eq(sitemap_lines)
+      end
+    end
+  end
+end