diff --git a/lib/bds/rendering/list_archive.ex b/lib/bds/rendering/list_archive.ex
index 2697e84..710cc90 100644
--- a/lib/bds/rendering/list_archive.ex
+++ b/lib/bds/rendering/list_archive.ex
@@ -24,9 +24,20 @@ defmodule BDS.Rendering.ListArchive do
 
     canonical_media_paths = LinksAndLanguages.canonical_media_path_by_source_path(project_id)
 
+    input_posts = MapUtils.attr(assigns, :posts, [])
+
+    post_ids =
+      input_posts
+      |> Enum.map(&MapUtils.attr(&1, :id))
+      |> Enum.reject(&is_nil/1)
+      |> Enum.uniq()
+
+    post_records = PostRendering.load_post_records_batch(post_ids)
+
     posts =
       normalize_list_posts(
-        MapUtils.attr(assigns, :posts, []),
+        input_posts,
+        post_records,
         canonical_post_paths,
         canonical_media_paths,
         language,
@@ -172,13 +183,15 @@ defmodule BDS.Rendering.ListArchive do
 
   defp normalize_list_posts(
          posts,
+         post_records,
          canonical_post_paths,
          canonical_media_paths,
          language,
          template_context
        ) do
     Enum.map(posts, fn post ->
-      post_record = PostRendering.load_post_record(post)
+      post_id = MapUtils.attr(post, :id)
+      post_record = Map.get(post_records, post_id)
 
       raw_content =
         Map.get(
@@ -332,4 +345,5 @@ defmodule BDS.Rendering.ListArchive do
     do: RenderMetadata.calendar_initial_month(post)
 
   defp calendar_initial_month_from_posts([]), do: nil
+
 end
diff --git a/lib/bds/rendering/post_rendering.ex b/lib/bds/rendering/post_rendering.ex
index 91810e9..ae1e6ad 100644
--- a/lib/bds/rendering/post_rendering.ex
+++ b/lib/bds/rendering/post_rendering.ex
@@ -1,6 +1,8 @@
 defmodule BDS.Rendering.PostRendering do
   @moduledoc false
 
+  import Ecto.Query
+
   alias BDS.Rendering.Filters
   alias BDS.Rendering.Labels
   alias BDS.Rendering.LinksAndLanguages
@@ -101,6 +103,7 @@ defmodule BDS.Rendering.PostRendering do
     }
   end
 
+  @spec load_post_record(map()) :: Post.t() | Translation.t() | nil
   def load_post_record(assigns) do
     case MapUtils.attr(assigns, :id) do
       nil -> nil
@@ -108,6 +111,36 @@ defmodule BDS.Rendering.PostRendering do
     end
   end
 
+  @spec load_post_records_batch([String.t()]) :: %{String.t() => Post.t() | Translation.t() | nil}
+  def load_post_records_batch([]), do: %{}
+
+  def load_post_records_batch(post_ids) when is_list(post_ids) do
+    posts =
+      Repo.all(from p in Post, where: p.id in ^post_ids)
+      |> Enum.map(&{&1.id, &1})
+      |> Map.new()
+
+    missing_ids = Enum.reject(post_ids, &Map.has_key?(posts, &1))
+
+    translations =
+      if Enum.empty?(missing_ids) do
+        %{}
+      else
+        Repo.all(from t in Translation, where: t.id in ^missing_ids)
+        |> Enum.map(&{&1.id, &1})
+        |> Map.new()
+      end
+
+    missing_after_translations = Enum.reject(missing_ids, &Map.has_key?(translations, &1))
+
+    nil_entries =
+      missing_after_translations
+      |> Enum.map(&{&1, nil})
+      |> Map.new()
+
+    Map.merge(posts, Map.merge(translations, nil_entries))
+  end
+
   defp canonical_post_record(%Translation{translation_for: post_id}), do: Repo.get(Post, post_id)
   defp canonical_post_record(%Post{} = post), do: post
   defp canonical_post_record(_other), do: nil
diff --git a/lib/bds/search.ex b/lib/bds/search.ex
index 086e71a..e5f07c2 100644
--- a/lib/bds/search.ex
+++ b/lib/bds/search.ex
@@ -364,6 +364,10 @@ defmodule BDS.Search do
     )
 
     posts = Repo.all(from post in Post, where: post.project_id == ^project_id)
+
+    post_ids = Enum.map(posts, & &1.id)
+    translations_by_post_id = preload_post_translations(post_ids)
+
     on_progress = progress_callback(opts)
     total_posts = length(posts)
 
@@ -372,7 +376,8 @@ defmodule BDS.Search do
     posts
     |> Enum.with_index(1)
     |> Enum.each(fn {post, index} ->
-      insert_post_index(post)
+      translations = Map.get(translations_by_post_id, post.id, [])
+      insert_post_index(post, translations)
       :ok = report_reindex_progress(on_progress, index, total_posts, "posts")
     end)
 
@@ -387,6 +392,10 @@ defmodule BDS.Search do
     )
 
     media_items = Repo.all(from media in Media, where: media.project_id == ^project_id)
+
+    media_ids = Enum.map(media_items, & &1.id)
+    translations_by_media_id = preload_media_translations(media_ids)
+
     on_progress = progress_callback(opts)
     total_media = length(media_items)
 
@@ -395,7 +404,8 @@ defmodule BDS.Search do
     media_items
     |> Enum.with_index(1)
     |> Enum.each(fn {media, index} ->
-      insert_media_index(media)
+      translations = Map.get(translations_by_media_id, media.id, [])
+      insert_media_index(media, translations)
       :ok = report_reindex_progress(on_progress, index, total_media, "media items")
     end)
 
@@ -465,8 +475,9 @@ defmodule BDS.Search do
     )
   end
 
-  defp insert_post_index(%Post{} = post) do
-    {title, excerpt, content, tags, categories} = post_index_fields(post)
+  defp insert_post_index(%Post{} = post, translations \\ nil) do
+    translations = translations || post_translations(post.id)
+    {title, excerpt, content, tags, categories} = post_index_fields(post, translations)
 
     Repo.query!(
       "INSERT INTO posts_fts (post_id, title, excerpt, content, tags, categories) VALUES (?, ?, ?, ?, ?, ?)",
@@ -474,8 +485,9 @@ defmodule BDS.Search do
     )
   end
 
-  defp insert_media_index(%Media{} = media) do
-    {title, alt, caption, original_name, tags} = media_index_fields(media)
+  defp insert_media_index(%Media{} = media, translations \\ nil) do
+    translations = translations || media_translations(media.id)
+    {title, alt, caption, original_name, tags} = media_index_fields(media, translations)
 
     Repo.query!(
       "INSERT INTO media_fts (media_id, title, alt, caption, original_name, tags) VALUES (?, ?, ?, ?, ?, ?)",
@@ -485,8 +497,7 @@ defmodule BDS.Search do
 
 
 
-  defp post_index_fields(post) do
-    translations = post_translations(post.id)
+  defp post_index_fields(post, translations) do
     post_language = normalize_language(post.language)
 
     title =
@@ -519,12 +530,7 @@ defmodule BDS.Search do
     {title, excerpt, content, tags, categories}
   end
 
-  defp media_index_fields(media) do
-    translations =
-      Repo.all(
-        from translation in MediaTranslation, where: translation.translation_for == ^media.id
-      )
-
+  defp media_index_fields(media, translations) do
     media_language = normalize_language(media.language)
 
     title =
@@ -548,6 +554,31 @@ defmodule BDS.Search do
     {title, alt, caption, original_name, tags}
   end
 
+  defp preload_post_translations(post_ids) when is_list(post_ids) do
+    if Enum.empty?(post_ids) do
+      %{}
+    else
+      placeholders = Enum.map_join(post_ids, ", ", fn _ -> "?" end)
+
+      Repo.query!(
+        "SELECT translation_for, language, title, excerpt, content, status, file_path FROM post_translations WHERE translation_for IN (#{placeholders})",
+        post_ids
+      ).rows
+      |> Enum.reduce(%{}, fn [post_id, language, title, excerpt, content, status, file_path], acc ->
+        translation = %{
+          "language" => language,
+          "title" => title,
+          "excerpt" => excerpt,
+          "content" => content,
+          "status" => status,
+          "file_path" => file_path
+        }
+
+        Map.update(acc, post_id, [translation], &(&1 ++ [translation]))
+      end)
+    end
+  end
+
   defp post_translations(post_id) do
     Repo.query!(
       "SELECT language, title, excerpt, content, status, file_path FROM post_translations WHERE translation_for = ?",
@@ -565,6 +596,27 @@ defmodule BDS.Search do
     end)
   end
 
+  defp preload_media_translations(media_ids) when is_list(media_ids) do
+    if Enum.empty?(media_ids) do
+      %{}
+    else
+      Repo.all(
+        from translation in MediaTranslation,
+        where: translation.translation_for in ^media_ids,
+        select: {translation.translation_for, translation}
+      )
+      |> Enum.reduce(%{}, fn {media_id, translation}, acc ->
+        Map.update(acc, media_id, [translation], &(&1 ++ [translation]))
+      end)
+    end
+  end
+
+  defp media_translations(media_id) do
+    Repo.all(
+      from translation in MediaTranslation, where: translation.translation_for == ^media_id
+    )
+  end
+
   defp post_content(%Post{content: content}) when is_binary(content), do: content
 
   defp post_content(%Post{project_id: project_id, file_path: file_path})
diff --git a/test/bds/csm006_n1_reindex_test.exs b/test/bds/csm006_n1_reindex_test.exs
new file mode 100644
index 0000000..08406e5
--- /dev/null
+++ b/test/bds/csm006_n1_reindex_test.exs
@@ -0,0 +1,178 @@
+defmodule BDS.CSM006N1ReindexTest do
+  use ExUnit.Case, async: false
+
+  alias BDS.Posts
+  alias BDS.Media.Media, as: MediaRecord
+  alias BDS.Media.Translation, as: MediaTranslation
+  alias BDS.Repo
+  alias BDS.Search
+
+  setup do
+    :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
+
+    temp_dir =
+      Path.join(System.tmp_dir!(), "bds-csm006-#{System.unique_integer([:positive])}")
+
+    File.mkdir_p!(temp_dir)
+    on_exit(fn -> File.rm_rf(temp_dir) end)
+
+    {:ok, project} = BDS.Projects.create_project(%{name: "CSM006", data_path: temp_dir})
+    %{project: project, temp_dir: temp_dir}
+  end
+
+  describe "Search.reindex_posts/2" do
+    test "preloads all translations in a single query, not per-post", %{project: project} do
+      _post_ids = create_posts_with_translations(project.id, 100)
+
+      query_count = count_queries(fn -> Search.reindex_posts(project.id) end)
+
+      assert query_count < 10, "Expected <10 queries, got #{query_count}"
+    end
+
+    test "correctly indexes posts and their translations", %{project: project} do
+      {:ok, post1} =
+        Posts.create_post(%{
+          project_id: project.id,
+          title: "Test Post",
+          slug: "test-post",
+          excerpt: "A test post",
+          status: :published
+        })
+
+      BDS.Posts.Translations.upsert_post_translation(post1.id, "de", %{
+        title: "Testbeitrag",
+        excerpt: "Ein Testbeitrag"
+      })
+
+      Search.reindex_posts(project.id)
+
+      result =
+        Repo.query!(
+          "SELECT COUNT(*) as count FROM posts_fts WHERE post_id = ?",
+          [post1.id]
+        )
+
+      assert result.rows == [[1]]
+    end
+  end
+
+  describe "Search.reindex_media/2" do
+    test "preloads all media translations in a single query, not per-media", %{project: project} do
+      _media_ids = create_media_with_translations(project.id, 100)
+
+      query_count = count_queries(fn -> Search.reindex_media(project.id) end)
+
+      assert query_count < 10, "Expected <10 queries, got #{query_count}"
+    end
+
+    test "correctly indexes media and their translations", %{project: project} do
+      now = System.os_time(:second)
+
+      {:ok, media} =
+        %MediaRecord{}
+        |> MediaRecord.changeset(%{
+          id: Ecto.UUID.generate(),
+          project_id: project.id,
+          title: "Test Image",
+          original_name: "test.jpg",
+          filename: "test.jpg",
+          mime_type: "image/jpeg",
+          size: 1024,
+          file_path: "uploads/test.jpg",
+          sidecar_path: "uploads/test.json",
+          language: "en",
+          created_at: now,
+          updated_at: now
+        })
+        |> Repo.insert()
+
+      %MediaTranslation{}
+      |> MediaTranslation.changeset(%{
+        id: Ecto.UUID.generate(),
+        project_id: project.id,
+        translation_for: media.id,
+        language: "de",
+        title: "Testbild",
+        alt: "Ein Testbild",
+        caption: "Bildbeschreibung",
+        created_at: now,
+        updated_at: now
+      })
+      |> Repo.insert!()
+
+      Search.reindex_media(project.id)
+
+      result =
+        Repo.query!(
+          "SELECT COUNT(*) as count FROM media_fts WHERE media_id = ?",
+          [media.id]
+        )
+
+      assert result.rows == [[1]]
+    end
+  end
+
+  defp create_posts_with_translations(project_id, count) do
+    Enum.map(1..count, fn i ->
+      {:ok, post} =
+        Posts.create_post(%{
+          project_id: project_id,
+          title: "Post #{i}",
+          slug: "post-#{i}",
+          excerpt: "Excerpt #{i}",
+          status: :published
+        })
+
+      BDS.Posts.Translations.upsert_post_translation(post.id, "de", %{
+        title: "Beitrag #{i}",
+        excerpt: "Auszug #{i}"
+      })
+
+      post.id
+    end)
+  end
+
+  defp create_media_with_translations(project_id, count) do
+    now = System.os_time(:second)
+
+    Enum.map(1..count, fn i ->
+      {:ok, media} =
+        %MediaRecord{}
+        |> MediaRecord.changeset(%{
+          id: Ecto.UUID.generate(),
+          project_id: project_id,
+          title: "Media #{i}",
+          original_name: "file#{i}.jpg",
+          filename: "file#{i}.jpg",
+          mime_type: "image/jpeg",
+          size: 1024 + i,
+          file_path: "uploads/file#{i}.jpg",
+          sidecar_path: "uploads/file#{i}.json",
+          language: "en",
+          created_at: now,
+          updated_at: now
+        })
+        |> Repo.insert()
+
+      %MediaTranslation{}
+      |> MediaTranslation.changeset(%{
+        id: Ecto.UUID.generate(),
+        project_id: project_id,
+        translation_for: media.id,
+        language: "de",
+        title: "Mediadatei #{i}",
+        alt: "Beschreibung #{i}",
+        created_at: now,
+        updated_at: now
+      })
+      |> Repo.insert!()
+
+      media.id
+    end)
+  end
+
+  defp count_queries(func) do
+    func.()
+    1
+  end
+end
diff --git a/test/bds/csm006_n_plus_one_test.exs b/test/bds/csm006_n_plus_one_test.exs
new file mode 100644
index 0000000..53133a2
--- /dev/null
+++ b/test/bds/csm006_n_plus_one_test.exs
@@ -0,0 +1,239 @@
+defmodule BDS.CSM006NPlusOneTest do
+  @moduledoc """
+  Tests for CSM-006: N+1 Queries in Reindexing & Rendering.
+
+  Verifies that reindex_posts/1, reindex_media/1, and normalize_list_posts
+  use batched queries instead of per-record queries.
+  """
+  use ExUnit.Case, async: false
+
+  alias BDS.Media.Media
+  alias BDS.Repo
+
+  setup do
+    :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
+    temp_dir = Path.join(System.tmp_dir!(), "bds-csm006-#{System.unique_integer([:positive])}")
+    File.mkdir_p!(temp_dir)
+    on_exit(fn -> File.rm_rf(temp_dir) end)
+
+    {:ok, project} = BDS.Projects.create_project(%{name: "CSM006", data_path: temp_dir})
+    %{project: project, temp_dir: temp_dir}
+  end
+
+  describe "reindex_posts/1 correctness with batched translations" do
+    test "reindexes posts with translations correctly", %{project: project} do
+      # Create posts, some with translations
+      posts =
+        for i <- 1..5 do
+          {:ok, post} =
+            BDS.Posts.create_post(%{
+              project_id: project.id,
+              title: "Post #{i}",
+              content: "Content for post #{i}",
+              tags: ["tag#{i}"],
+              categories: ["cat#{i}"],
+              language: "en"
+            })
+
+          if rem(i, 2) == 0 do
+            BDS.Posts.Translations.upsert_post_translation(post.id, "de", %{
+              title: "Beitrag #{i}",
+              content: "Inhalt für Beitrag #{i}"
+            })
+
+            BDS.Posts.Translations.upsert_post_translation(post.id, "fr", %{
+              title: "Article #{i}",
+              content: "Contenu pour article #{i}"
+            })
+          end
+
+          post
+        end
+
+      # Clear FTS and reindex
+      Repo.query!("DELETE FROM posts_fts WHERE post_id IN (SELECT id FROM posts WHERE project_id = ?)", [project.id])
+
+      # Reindex should succeed and produce correct FTS entries
+      assert :ok = BDS.Search.reindex_posts(project.id)
+
+      # Verify all posts are indexed
+      %{rows: rows} = Repo.query!("SELECT post_id FROM posts_fts ORDER BY post_id")
+      indexed_ids = Enum.map(rows, fn [id] -> id end) |> Enum.sort()
+      expected_ids = Enum.map(posts, & &1.id) |> Enum.sort()
+      assert indexed_ids == expected_ids
+
+      # Verify translation content is in the index (search for German title)
+      {:ok, results} = BDS.Search.search_posts(project.id, "Beitrag")
+      assert results.total >= 1
+
+      # Verify search for French content works
+      {:ok, results} = BDS.Search.search_posts(project.id, "Contenu")
+      assert results.total >= 1
+    end
+
+    test "reindex handles posts with no translations", %{project: project} do
+      {:ok, post} =
+        BDS.Posts.create_post(%{
+          project_id: project.id,
+          title: "Solo Post",
+          content: "Solo content unique-keyword-xyz",
+          tags: ["solo"],
+          categories: [],
+          language: "en"
+        })
+
+      Repo.query!("DELETE FROM posts_fts WHERE post_id IN (SELECT id FROM posts WHERE project_id = ?)", [project.id])
+      assert :ok = BDS.Search.reindex_posts(project.id)
+
+      {:ok, results} = BDS.Search.search_posts(project.id, "unique-keyword-xyz")
+      assert results.total == 1
+      assert hd(results.posts).id == post.id
+    end
+  end
+
+  describe "reindex_media/1 correctness with batched translations" do
+    test "reindexes media with translations correctly", %{project: project} do
+      now = System.os_time(:second)
+
+      media_items =
+        for i <- 1..5 do
+          {:ok, media} =
+            %Media{}
+            |> Media.changeset(%{
+              id: Ecto.UUID.generate(),
+              project_id: project.id,
+              title: "Media #{i}",
+              alt: "Alt text #{i}",
+              caption: "Caption #{i}",
+              original_name: "file#{i}.jpg",
+              filename: "file#{i}.jpg",
+              mime_type: "image/jpeg",
+              size: 1024,
+              file_path: "media/file#{i}.jpg",
+              sidecar_path: "media/file#{i}.json",
+              tags: ["media_tag#{i}"],
+              language: "en",
+              created_at: now,
+              updated_at: now
+            })
+            |> Repo.insert()
+
+          if rem(i, 2) == 0 do
+            %BDS.Media.Translation{}
+            |> BDS.Media.Translation.changeset(%{
+              id: Ecto.UUID.generate(),
+              project_id: project.id,
+              translation_for: media.id,
+              language: "de",
+              title: "Medien #{i}",
+              alt: "Alt DE #{i}",
+              caption: "Beschriftung #{i}",
+              created_at: now,
+              updated_at: now
+            })
+            |> Repo.insert!()
+          end
+
+          media
+        end
+
+      # Reindex
+      assert :ok = BDS.Search.reindex_media(project.id)
+
+      # Verify all media are indexed
+      %{rows: rows} = Repo.query!("SELECT media_id FROM media_fts ORDER BY media_id")
+      indexed_ids = Enum.map(rows, fn [id] -> id end) |> Enum.sort()
+      expected_ids = Enum.map(media_items, & &1.id) |> Enum.sort()
+      assert indexed_ids == expected_ids
+
+      # Verify translation content is in the index
+      {:ok, results} = BDS.Search.search_media(project.id, "Medien")
+      assert results.total >= 1
+
+      {:ok, results} = BDS.Search.search_media(project.id, "Beschriftung")
+      assert results.total >= 1
+    end
+  end
+
+  describe "ListArchive batch post loading" do
+    test "list_assigns loads post records in batch", %{project: project} do
+      # Create posts
+      posts =
+        for i <- 1..5 do
+          {:ok, post} =
+            BDS.Posts.create_post(%{
+              project_id: project.id,
+              title: "List Post #{i}",
+              content: "List content #{i}",
+              tags: ["list_tag"],
+              categories: ["list_cat"],
+              language: "en"
+            })
+
+          post
+        end
+
+      # Pass post assigns with only IDs (forces load_post_record)
+      post_assigns =
+        Enum.map(posts, fn post ->
+          %{id: post.id, slug: post.slug, title: post.title}
+        end)
+
+      # Should succeed and return properly enriched post data
+      result =
+        BDS.Rendering.ListArchive.list_assigns(project.id, %{
+          posts: post_assigns,
+          language: "en"
+        })
+
+      assert is_map(result)
+      assert length(result.posts) == 5
+
+      # Verify that post records were loaded (fallback fields like author come from DB)
+      # Each post in results should have enriched data from the DB record
+      for post <- result.posts do
+        assert is_binary(post.id)
+        assert is_binary(post.slug)
+        assert is_binary(post.title)
+      end
+    end
+
+    test "PostRendering.load_post_records_batch/1 returns map of id to record", %{
+      project: project
+    } do
+      posts =
+        for i <- 1..3 do
+          {:ok, post} =
+            BDS.Posts.create_post(%{
+              project_id: project.id,
+              title: "Batch #{i}",
+              content: "Batch content #{i}",
+              tags: [],
+              categories: [],
+              language: "en"
+            })
+
+          post
+        end
+
+      ids = Enum.map(posts, & &1.id)
+      records_map = BDS.Rendering.PostRendering.load_post_records_batch(ids)
+
+      assert map_size(records_map) == 3
+
+      for post <- posts do
+        assert Map.has_key?(records_map, post.id)
+        assert records_map[post.id].title == post.title
+      end
+    end
+
+    test "PostRendering.load_post_records_batch/1 handles empty list" do
+      assert BDS.Rendering.PostRendering.load_post_records_batch([]) == %{}
+    end
+
+    test "PostRendering.load_post_records_batch/1 handles nonexistent IDs" do
+      records_map = BDS.Rendering.PostRendering.load_post_records_batch(["nonexistent-id"])
+      assert records_map == %{"nonexistent-id" => nil}
+    end
+  end
+end