diff --git a/lib/bds/desktop/shell_live/post_editor.ex b/lib/bds/desktop/shell_live/post_editor.ex
index b0aef77..feb45aa 100644
--- a/lib/bds/desktop/shell_live/post_editor.ex
+++ b/lib/bds/desktop/shell_live/post_editor.ex
@@ -6,11 +6,11 @@ defmodule BDS.Desktop.ShellLive.PostEditor do
   alias BDS.{AI, Embeddings, Metadata, Posts, Preview, Tasks}
   alias BDS.Desktop.ShellData
   alias BDS.Desktop.ShellLive.{EditorImageDrop, Notify}
-  alias BDS.Desktop.ShellLive.PostEditor.{DraftManagement, ListValues, Persistence, PostMetadata}
   alias BDS.Posts.Post
   alias BDS.Tags
+  alias BDS.UI.PostEditor.{Draft, ListValues, Persistence}
 
-  import DraftManagement,
+  import Draft,
     only: [
       editing_canonical_language?: 3,
       normalize_language: 2,
@@ -48,7 +48,7 @@ defmodule BDS.Desktop.ShellLive.PostEditor do
 
   use Gettext, backend: BDS.Gettext
 
-  import PostMetadata,
+  import BDS.UI.PostEditor.Metadata,
     only: [
       blank?: 1,
       blank_to_nil: 1,
diff --git a/lib/bds/desktop/shell_live/post_editor/draft_management.ex b/lib/bds/desktop/shell_live/post_editor/draft_management.ex
deleted file mode 100644
index 6869356..0000000
--- a/lib/bds/desktop/shell_live/post_editor/draft_management.ex
+++ /dev/null
@@ -1,241 +0,0 @@
-defmodule BDS.Desktop.ShellLive.PostEditor.DraftManagement do
-  @moduledoc false
-
-  import Phoenix.Component, only: [assign: 3]
-
-  alias BDS.Posts
-  alias BDS.Posts.{Post, Translation}
-  alias BDS.Desktop.ShellLive.PostEditor.PostMetadata
-  alias BDS.UI.Workbench
-
-  @spec normalize_mode(term()) :: term()
-  def normalize_mode(mode) when mode in [:markdown, :preview], do: mode
-  @spec normalize_mode(term()) :: term()
-  def normalize_mode("visual"), do: :markdown
-  def normalize_mode("preview"), do: :preview
-  def normalize_mode(_mode), do: :markdown
-
-  @spec normalize_language(term(), term()) :: term()
-  def normalize_language(value, fallback) do
-    case value |> to_string() |> String.trim() do
-      "" -> fallback
-      normalized -> String.downcase(normalized)
-    end
-  end
-
-  @spec normalize_params(term(), term(), term()) :: term()
-  def normalize_params(params, current_language, next_language) do
-    %{
-      "title" => Map.get(params, "title", ""),
-      "excerpt" => Map.get(params, "excerpt", ""),
-      "content" => Map.get(params, "content", ""),
-      "tags" => Map.get(params, "tags", ""),
-      "categories" => Map.get(params, "categories", ""),
-      "author" => Map.get(params, "author", ""),
-      "language" =>
-        if(current_language == next_language,
-          do: normalize_language(Map.get(params, "language"), current_language),
-          else: next_language
-        ),
-      "do_not_translate" => truthy?(Map.get(params, "do_not_translate")),
-      "template_slug" => Map.get(params, "template_slug", "")
-    }
-  end
-
-  @spec current_draft(term(), term(), term(), term()) :: term()
-  def current_draft(assigns, %Post{} = post, metadata, active_language) do
-    persisted = persisted_form(post, metadata, active_language)
-
-    assigns.post_editor_drafts
-    |> Map.get(post.id, %{})
-    |> Map.get(active_language, persisted)
-  end
-
-  @spec persisted_form(term(), term(), term()) :: term()
-  def persisted_form(%Post{} = post, metadata, active_language) do
-    persisted_form(post, metadata, active_language, PostMetadata.translations(post.id))
-  end
-
-  @spec persisted_form(term(), term(), term(), term()) :: term()
-  def persisted_form(post, metadata, active_language, translations) do
-    canonical_language = PostMetadata.canonical_language(post, metadata)
-    translation = Map.get(translations, active_language)
-
-    if active_language == canonical_language do
-      %{
-        "title" => post.title || "",
-        "excerpt" => post.excerpt || "",
-        "content" => Posts.editor_body(post),
-        "tags" => Enum.join(post.tags || [], ", "),
-        "categories" => Enum.join(post.categories || [], ", "),
-        "author" => post.author || metadata.default_author || "",
-        "language" => canonical_language,
-        "do_not_translate" => post.do_not_translate || false,
-        "template_slug" => post.template_slug || ""
-      }
-    else
-      %{
-        "title" => (translation && translation.title) || "",
-        "excerpt" => (translation && translation.excerpt) || "",
-        "content" => if(translation, do: Posts.editor_body(translation), else: ""),
-        "tags" => Enum.join(post.tags || [], ", "),
-        "categories" => Enum.join(post.categories || [], ", "),
-        "author" => post.author || metadata.default_author || "",
-        "language" => active_language,
-        "do_not_translate" => post.do_not_translate || false,
-        "template_slug" => post.template_slug || ""
-      }
-    end
-  end
-
-  @spec maybe_update_draft(term(), term(), term(), term(), term(), term(), term()) :: term()
-  def maybe_update_draft(socket, post_id, post, current_language, next_language, draft, true) do
-    workbench = Workbench.mark_dirty(socket.assigns.workbench, :post, post_id)
-
-    socket
-    |> assign(:workbench, workbench)
-    |> assign(
-      :post_editor_drafts,
-      put_nested_map(socket.assigns.post_editor_drafts, post_id, next_language, draft)
-    )
-    |> assign(
-      :post_editor_active_languages,
-      Map.put(socket.assigns.post_editor_active_languages, post_id, next_language)
-    )
-    |> assign(
-      :post_editor_save_states,
-      Map.put(socket.assigns.post_editor_save_states, post_id, :dirty)
-    )
-    |> assign(
-      :tab_meta,
-      Map.put(socket.assigns.tab_meta, {:post, post_id}, %{
-        title: draft["title"],
-        subtitle: Atom.to_string(post.status || :draft)
-      })
-    )
-    |> maybe_drop_old_language_draft(post_id, current_language, next_language)
-  end
-
-  def maybe_update_draft(socket, post_id, _post, _current_language, next_language, _draft, false) do
-    assign(
-      socket,
-      :post_editor_active_languages,
-      Map.put(socket.assigns.post_editor_active_languages, post_id, next_language)
-    )
-  end
-
-  @spec put_draft_field(term(), term(), term(), term(), term(), term()) :: term()
-  def put_draft_field(socket, post_id, post, active_language, field, value) do
-    metadata = PostMetadata.project_metadata(post.project_id)
-    draft = Map.put(current_draft(socket.assigns, post, metadata, active_language), field, value)
-    workbench = Workbench.mark_dirty(socket.assigns.workbench, :post, post_id)
-
-    socket
-    |> assign(:workbench, workbench)
-    |> assign(
-      :post_editor_drafts,
-      put_nested_map(socket.assigns.post_editor_drafts, post_id, active_language, draft)
-    )
-    |> assign(
-      :post_editor_save_states,
-      Map.put(socket.assigns.post_editor_save_states, post_id, :dirty)
-    )
-  end
-
-  @spec put_query_state(term(), term(), term(), term()) :: term()
-  def put_query_state(socket, post_id, kind, value) do
-    key = query_key(kind)
-
-    assign(
-      socket,
-      key,
-      Map.put(Map.get(socket.assigns, key, %{}), post_id, to_string(value || ""))
-    )
-  end
-
-  @spec query_value(term(), term(), term()) :: term()
-  def query_value(assigns, kind, post_id) do
-    assigns
-    |> Map.get(query_key(kind), %{})
-    |> Map.get(post_id, "")
-  end
-
-  defp query_key(:tags), do: :post_editor_tag_queries
-  defp query_key(:categories), do: :post_editor_category_queries
-
-  defp maybe_drop_old_language_draft(socket, _post_id, current_language, next_language)
-       when current_language == next_language,
-       do: socket
-
-  defp maybe_drop_old_language_draft(socket, post_id, current_language, _next_language) do
-    assign(
-      socket,
-      :post_editor_drafts,
-      delete_nested_map(socket.assigns.post_editor_drafts, post_id, current_language)
-    )
-  end
-
-  @spec toggled_sections(term(), term(), term()) :: term()
-  def toggled_sections(expanded_by_post, post_id, section) do
-    expanded_by_post
-    |> Map.get(post_id, %{metadata: false, excerpt: false})
-    |> Map.put_new(:metadata, false)
-    |> Map.put_new(:excerpt, false)
-    |> Map.update!(section, &(not &1))
-  end
-
-  @spec put_nested_map(term(), term(), term(), term()) :: term()
-  def put_nested_map(map, key, nested_key, value) do
-    Map.update(map, key, %{nested_key => value}, &Map.put(&1, nested_key, value))
-  end
-
-  @spec delete_nested_map(term(), term(), term()) :: term()
-  def delete_nested_map(map, key, nested_key) do
-    case Map.get(map, key) do
-      nil ->
-        map
-
-      nested ->
-        case Map.delete(nested, nested_key) do
-          emptied when map_size(emptied) == 0 -> Map.delete(map, key)
-          remaining -> Map.put(map, key, remaining)
-        end
-    end
-  end
-
-  @spec reload_with_assigned_workbench(term(), term()) :: term()
-  def reload_with_assigned_workbench(socket, reload),
-    do: reload.(socket, socket.assigns.workbench)
-
-  @spec save_state_for_action(term()) :: term()
-  def save_state_for_action(:publish), do: :published
-  def save_state_for_action(_action), do: :saved
-
-  @spec record_title(term(), term()) :: term()
-  def record_title(%Translation{title: title}, post),
-    do: blank_to_nil(title) || post.title || post.slug || post.id
-
-  def record_title(%Post{title: title, slug: slug, id: id}, _post),
-    do: blank_to_nil(title) || blank_to_nil(slug) || id
-
-  @spec record_status(term()) :: term()
-  def record_status(%Translation{status: status}), do: status || :draft
-  def record_status(%Post{status: status}), do: status || :draft
-
-  @spec editing_canonical_language?(term(), term(), term()) :: term()
-  def editing_canonical_language?(translations, active_language, canonical_language) do
-    active_language == canonical_language or not Map.has_key?(translations, active_language)
-  end
-
-  defp truthy?(value), do: BDS.Values.truthy?(value)
-
-  defp blank_to_nil(value) do
-    value
-    |> to_string()
-    |> String.trim()
-    |> case do
-      "" -> nil
-      trimmed -> trimmed
-    end
-  end
-end
diff --git a/lib/bds/ui/post_editor/draft.ex b/lib/bds/ui/post_editor/draft.ex
new file mode 100644
index 0000000..51b24e8
--- /dev/null
+++ b/lib/bds/ui/post_editor/draft.ex
@@ -0,0 +1,107 @@
+defmodule BDS.UI.PostEditor.Draft do
+  @moduledoc """
+  Pure draft/form logic for the post editor (issue #26, phase 3).
+
+  Shared by the LiveView shell and the TUI: builds the persisted form for a
+  post (canonical language or translation), normalizes editor params, and
+  provides the small pure helpers both renderers need. No socket, no
+  process state — callers own the draft maps.
+  """
+
+  alias BDS.Posts
+  alias BDS.Posts.{Post, Translation}
+  alias BDS.UI.PostEditor.Metadata
+
+  def normalize_mode(mode) when mode in [:markdown, :preview], do: mode
+  def normalize_mode("visual"), do: :markdown
+  def normalize_mode("preview"), do: :preview
+  def normalize_mode(_mode), do: :markdown
+
+  def normalize_language(value, fallback) do
+    case value |> to_string() |> String.trim() do
+      "" -> fallback
+      normalized -> String.downcase(normalized)
+    end
+  end
+
+  def normalize_params(params, current_language, next_language) do
+    %{
+      "title" => Map.get(params, "title", ""),
+      "excerpt" => Map.get(params, "excerpt", ""),
+      "content" => Map.get(params, "content", ""),
+      "tags" => Map.get(params, "tags", ""),
+      "categories" => Map.get(params, "categories", ""),
+      "author" => Map.get(params, "author", ""),
+      "language" =>
+        if(current_language == next_language,
+          do: normalize_language(Map.get(params, "language"), current_language),
+          else: next_language
+        ),
+      "do_not_translate" => truthy?(Map.get(params, "do_not_translate")),
+      "template_slug" => Map.get(params, "template_slug", "")
+    }
+  end
+
+  def persisted_form(%Post{} = post, metadata, active_language) do
+    persisted_form(post, metadata, active_language, Metadata.translations(post.id))
+  end
+
+  def persisted_form(post, metadata, active_language, translations) do
+    canonical_language = Metadata.canonical_language(post, metadata)
+    translation = Map.get(translations, active_language)
+
+    if active_language == canonical_language do
+      %{
+        "title" => post.title || "",
+        "excerpt" => post.excerpt || "",
+        "content" => Posts.editor_body(post),
+        "tags" => Enum.join(post.tags || [], ", "),
+        "categories" => Enum.join(post.categories || [], ", "),
+        "author" => post.author || metadata.default_author || "",
+        "language" => canonical_language,
+        "do_not_translate" => post.do_not_translate || false,
+        "template_slug" => post.template_slug || ""
+      }
+    else
+      %{
+        "title" => (translation && translation.title) || "",
+        "excerpt" => (translation && translation.excerpt) || "",
+        "content" => if(translation, do: Posts.editor_body(translation), else: ""),
+        "tags" => Enum.join(post.tags || [], ", "),
+        "categories" => Enum.join(post.categories || [], ", "),
+        "author" => post.author || metadata.default_author || "",
+        "language" => active_language,
+        "do_not_translate" => post.do_not_translate || false,
+        "template_slug" => post.template_slug || ""
+      }
+    end
+  end
+
+  def save_state_for_action(:publish), do: :published
+  def save_state_for_action(_action), do: :saved
+
+  def record_title(%Translation{title: title}, post),
+    do: blank_to_nil(title) || post.title || post.slug || post.id
+
+  def record_title(%Post{title: title, slug: slug, id: id}, _post),
+    do: blank_to_nil(title) || blank_to_nil(slug) || id
+
+  def record_status(%Translation{status: status}), do: status || :draft
+  def record_status(%Post{status: status}), do: status || :draft
+
+  def editing_canonical_language?(translations, active_language, canonical_language) do
+    active_language == canonical_language or not Map.has_key?(translations, active_language)
+  end
+
+  defp truthy?(value), do: BDS.Values.truthy?(value)
+
+  defp blank_to_nil(value) do
+    value
+    |> to_string()
+    |> String.trim()
+    |> case do
+      "" -> nil
+      trimmed -> trimmed
+    end
+  end
+end
diff --git a/lib/bds/desktop/shell_live/post_editor/list_values.ex b/lib/bds/ui/post_editor/list_values.ex
similarity index 98%
rename from lib/bds/desktop/shell_live/post_editor/list_values.ex
rename to lib/bds/ui/post_editor/list_values.ex
index f187621..fe65254 100644
--- a/lib/bds/desktop/shell_live/post_editor/list_values.ex
+++ b/lib/bds/ui/post_editor/list_values.ex
@@ -1,4 +1,4 @@
-defmodule BDS.Desktop.ShellLive.PostEditor.ListValues do
+defmodule BDS.UI.PostEditor.ListValues do
   @moduledoc false
 
   alias BDS.{Metadata, Tags}
diff --git a/lib/bds/desktop/shell_live/post_editor/post_metadata.ex b/lib/bds/ui/post_editor/metadata.ex
similarity index 98%
rename from lib/bds/desktop/shell_live/post_editor/post_metadata.ex
rename to lib/bds/ui/post_editor/metadata.ex
index 3963ac1..05f4f90 100644
--- a/lib/bds/desktop/shell_live/post_editor/post_metadata.ex
+++ b/lib/bds/ui/post_editor/metadata.ex
@@ -1,4 +1,4 @@
-defmodule BDS.Desktop.ShellLive.PostEditor.PostMetadata do
+defmodule BDS.UI.PostEditor.Metadata do
   @moduledoc false
 
   import Ecto.Query
@@ -20,7 +20,7 @@ defmodule BDS.Desktop.ShellLive.PostEditor.PostMetadata do
 
   @spec canonical_language(term(), term()) :: term()
   def canonical_language(post, metadata) do
-    BDS.Desktop.ShellLive.PostEditor.DraftManagement.normalize_language(
+    BDS.UI.PostEditor.Draft.normalize_language(
       post.language,
       metadata.main_language || "en"
     )
diff --git a/lib/bds/desktop/shell_live/post_editor/persistence.ex b/lib/bds/ui/post_editor/persistence.ex
similarity index 83%
rename from lib/bds/desktop/shell_live/post_editor/persistence.ex
rename to lib/bds/ui/post_editor/persistence.ex
index 28fa9c2..1a9a1ca 100644
--- a/lib/bds/desktop/shell_live/post_editor/persistence.ex
+++ b/lib/bds/ui/post_editor/persistence.ex
@@ -1,17 +1,21 @@
-defmodule BDS.Desktop.ShellLive.PostEditor.Persistence do
-  @moduledoc false
+defmodule BDS.UI.PostEditor.Persistence do
+  @moduledoc """
+  Save/publish/discard workflow for post drafts, shared by the LiveView
+  shell and the TUI (issue #26, phase 3). Routes canonical-language edits
+  to the post itself and other languages to translations.
+  """
 
   alias BDS.Posts
   alias BDS.Posts.Post
-  alias BDS.Desktop.ShellLive.PostEditor.{DraftManagement, PostMetadata}
+  alias BDS.UI.PostEditor.{Draft, Metadata}
   use Gettext, backend: BDS.Gettext
 
   @spec persist(term(), term(), term(), term(), term()) :: term()
   def persist(%Post{} = post, draft, active_language, metadata, action) do
-    canonical_language = PostMetadata.canonical_language(post, metadata)
-    translations = PostMetadata.translations(post.id)
+    canonical_language = Metadata.canonical_language(post, metadata)
+    translations = Metadata.translations(post.id)
 
-    if DraftManagement.editing_canonical_language?(
+    if Draft.editing_canonical_language?(
          translations,
          active_language,
          canonical_language
@@ -28,11 +32,11 @@ defmodule BDS.Desktop.ShellLive.PostEditor.Persistence do
 
   @spec discard(term(), term(), term()) :: term()
   def discard(%Post{} = post, active_language, metadata) do
-    canonical_language = PostMetadata.canonical_language(post, metadata)
-    current_translations = PostMetadata.translations(post.id)
+    canonical_language = Metadata.canonical_language(post, metadata)
+    current_translations = Metadata.translations(post.id)
 
     cond do
-      not DraftManagement.editing_canonical_language?(
+      not Draft.editing_canonical_language?(
         current_translations,
         active_language,
         canonical_language
diff --git a/test/bds/gallery_pipeline_test.exs b/test/bds/gallery_pipeline_test.exs
index 5364de1..ecbf6f5 100644
--- a/test/bds/gallery_pipeline_test.exs
+++ b/test/bds/gallery_pipeline_test.exs
@@ -55,43 +55,43 @@ defmodule BDS.GalleryPipelineTest do
     test "counts [[gallery]] macro as gallery content" do
       form = %{"content" => "Some text\n\n[[gallery]]\n\nMore text"}
 
-      assert BDS.Desktop.ShellLive.PostEditor.PostMetadata.gallery_count(form) == 1
+      assert BDS.UI.PostEditor.Metadata.gallery_count(form) == 1
     end
 
     test "counts inline images as before" do
       form = %{"content" => "![Alt](image.jpg)"}
 
-      assert BDS.Desktop.ShellLive.PostEditor.PostMetadata.gallery_count(form) == 1
+      assert BDS.UI.PostEditor.Metadata.gallery_count(form) == 1
     end
 
     test "counts both [[gallery]] and inline images" do
       form = %{"content" => "![Alt](image.jpg)\n[[gallery]]"}
 
-      assert BDS.Desktop.ShellLive.PostEditor.PostMetadata.gallery_count(form) == 1
+      assert BDS.UI.PostEditor.Metadata.gallery_count(form) == 1
     end
 
     test "returns 0 when no gallery marks present" do
       form = %{"content" => "Just plain text"}
 
-      assert BDS.Desktop.ShellLive.PostEditor.PostMetadata.gallery_count(form) == 0
+      assert BDS.UI.PostEditor.Metadata.gallery_count(form) == 0
     end
 
     test "handles empty content" do
       form = %{}
 
-      assert BDS.Desktop.ShellLive.PostEditor.PostMetadata.gallery_count(form) == 0
+      assert BDS.UI.PostEditor.Metadata.gallery_count(form) == 0
     end
 
     test "counts multiple [[gallery]] occurrences" do
       form = %{"content" => "[[gallery]] some text [[gallery]]"}
 
-      assert BDS.Desktop.ShellLive.PostEditor.PostMetadata.gallery_count(form) == 2
+      assert BDS.UI.PostEditor.Metadata.gallery_count(form) == 2
     end
 
     test "is case insensitive for [[gallery]]" do
       form = %{"content" => "[[Gallery]]"}
 
-      assert BDS.Desktop.ShellLive.PostEditor.PostMetadata.gallery_count(form) == 1
+      assert BDS.UI.PostEditor.Metadata.gallery_count(form) == 1
     end
   end
 
diff --git a/test/bds/post_translations_test.exs b/test/bds/post_translations_test.exs
index 3b9298a..6b73d8d 100644
--- a/test/bds/post_translations_test.exs
+++ b/test/bds/post_translations_test.exs
@@ -220,7 +220,7 @@ defmodule BDS.PostTranslationsTest do
       "template_slug" => ""
     }
 
-    alias BDS.Desktop.ShellLive.PostEditor.Persistence
+    alias BDS.UI.PostEditor.Persistence
 
     assert {:ok, _post} = Persistence.persist(post, draft, "en", metadata, :auto_save)
     assert ai_tasks() == []
diff --git a/test/bds/ui/post_editor_test.exs b/test/bds/ui/post_editor_test.exs
new file mode 100644
index 0000000..0cde7ef
--- /dev/null
+++ b/test/bds/ui/post_editor_test.exs
@@ -0,0 +1,64 @@
+defmodule BDS.UI.PostEditorTest do
+  use ExUnit.Case, async: false
+
+  alias BDS.UI.PostEditor.{Draft, Metadata, Persistence}
+
+  setup do
+    :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
+
+    temp_dir = Path.join(System.tmp_dir!(), "bds-ui-pe-#{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: "UI PostEditor", data_path: temp_dir})
+
+    {:ok, post} =
+      BDS.Posts.create_post(%{
+        project_id: project.id,
+        title: "First Post",
+        content: "hello world",
+        tags: ["elixir"],
+        language: "en"
+      })
+
+    %{project: project, post: post}
+  end
+
+  test "persisted_form builds the canonical draft", %{post: post} do
+    metadata = Metadata.project_metadata(post.project_id)
+    form = Draft.persisted_form(post, metadata, "en")
+
+    assert form["title"] == "First Post"
+    assert form["content"] == "hello world"
+    assert form["tags"] == "elixir"
+    assert form["language"] == "en"
+  end
+
+  test "persist saves an edited draft and publish publishes it", %{post: post} do
+    metadata = Metadata.project_metadata(post.project_id)
+    form = Draft.persisted_form(post, metadata, "en")
+
+    draft = %{form | "title" => "Renamed Post", "content" => "updated body"}
+
+    assert {:ok, saved} = Persistence.persist(post, draft, "en", metadata, :save)
+    assert saved.title == "Renamed Post"
+    assert saved.status == :draft
+
+    form = Draft.persisted_form(saved, metadata, "en")
+    assert {:ok, published} = Persistence.persist(saved, form, "en", metadata, :publish)
+    assert published.status == :published
+    assert published.file_path != ""
+  end
+
+  test "discard on an unpublished draft is a no-op success", %{post: post} do
+    metadata = Metadata.project_metadata(post.project_id)
+    assert {:ok, _post} = Persistence.discard(post, "en", metadata)
+  end
+
+  test "normalize_params keeps the active language on same-language edits" do
+    params = %{"title" => "T", "language" => "DE "}
+
+    assert Draft.normalize_params(params, "de", "de")["language"] == "de"
+    assert Draft.normalize_params(params, "de", "fr")["language"] == "fr"
+  end
+end