diff --git a/lib/bds/frontmatter.ex b/lib/bds/frontmatter.ex
index b17c5e1..42063e3 100644
--- a/lib/bds/frontmatter.ex
+++ b/lib/bds/frontmatter.ex
@@ -1,6 +1,8 @@
 defmodule BDS.Frontmatter do
   @moduledoc false
 
+  @list_item_prefix "  - "
+
   def serialize_document(fields, body) when is_list(fields) do
     frontmatter =
       fields
@@ -11,6 +13,22 @@ defmodule BDS.Frontmatter do
     |> Enum.join("\n")
   end
 
+  def parse_document(contents) when is_binary(contents) do
+    case String.split(contents, "\n---\n", parts: 2) do
+      [frontmatter_with_marker, body] ->
+        frontmatter = String.replace_prefix(frontmatter_with_marker, "---\n", "")
+
+        {:ok,
+         %{
+           fields: parse_frontmatter(frontmatter),
+           body: String.trim_trailing(body, "\n")
+         }}
+
+      _parts ->
+        {:error, :invalid_frontmatter}
+    end
+  end
+
   defp serialize_field({_key, nil}), do: []
   defp serialize_field({_key, ""}), do: []
   defp serialize_field({_key, false}), do: []
@@ -26,4 +44,53 @@ defmodule BDS.Frontmatter do
   defp serialize_field({key, value}) do
     ["#{key}: #{value}"]
   end
+
+  defp parse_frontmatter(frontmatter) do
+    frontmatter
+    |> String.split("\n", trim: true)
+    |> parse_lines(%{})
+  end
+
+  defp parse_lines([], acc), do: acc
+
+  defp parse_lines([line | rest], acc) do
+    cond do
+      String.starts_with?(line, @list_item_prefix) ->
+        parse_lines(rest, acc)
+
+      String.ends_with?(line, ":") ->
+        key = String.trim_trailing(line, ":")
+        {items, remaining} = take_list_items(rest, [])
+        parse_lines(remaining, Map.put(acc, key, Enum.reverse(items)))
+
+      String.contains?(line, ": ") ->
+        [key, raw_value] = String.split(line, ": ", parts: 2)
+        parse_lines(rest, Map.put(acc, key, parse_scalar(raw_value)))
+
+      true ->
+        parse_lines(rest, acc)
+    end
+  end
+
+  defp take_list_items([line | rest], items) do
+    if String.starts_with?(line, @list_item_prefix) do
+      value = line |> String.replace_prefix(@list_item_prefix, "") |> parse_scalar()
+      take_list_items(rest, [value | items])
+    else
+      {items, [line | rest]}
+    end
+  end
+
+  defp take_list_items([], items), do: {items, []}
+
+  defp parse_scalar("true"), do: true
+  defp parse_scalar("false"), do: false
+
+  defp parse_scalar(value) do
+    if Regex.match?(~r/^-?\d+$/, value) do
+      String.to_integer(value)
+    else
+      value
+    end
+  end
 end
diff --git a/lib/bds/scripts.ex b/lib/bds/scripts.ex
index 39b105a..e60c585 100644
--- a/lib/bds/scripts.ex
+++ b/lib/bds/scripts.ex
@@ -104,6 +104,19 @@ defmodule BDS.Scripts do
     end
   end
 
+  def rebuild_scripts_from_files(project_id) do
+    project = Projects.get_project!(project_id)
+
+    scripts =
+      project
+      |> Projects.project_data_dir()
+      |> Path.join("scripts")
+      |> list_matching_files("*.lua")
+      |> Enum.map(&upsert_script_from_file(project_id, project, &1))
+
+    {:ok, scripts}
+  end
+
   defp default_entrypoint(:macro), do: "render"
   defp default_entrypoint(_kind), do: "main"
 
@@ -175,6 +188,48 @@ defmodule BDS.Scripts do
     end
   end
 
+  defp upsert_script_from_file(project_id, project, path) do
+    contents = File.read!(path)
+    {:ok, %{fields: fields}} = Frontmatter.parse_document(contents)
+    relative_path = Path.relative_to(path, Projects.project_data_dir(project))
+    now = System.system_time(:second)
+
+    attrs = %{
+      id: Map.get(fields, "id") || Ecto.UUID.generate(),
+      project_id: project_id,
+      slug: Map.fetch!(fields, "slug"),
+      title: Map.get(fields, "title") || "",
+      kind: parse_script_kind(Map.fetch!(fields, "kind")),
+      entrypoint: Map.get(fields, "entrypoint") || "main",
+      enabled: Map.get(fields, "enabled", true),
+      version: Map.get(fields, "version", 1),
+      file_path: relative_path,
+      status: :published,
+      content: nil,
+      created_at: Map.get(fields, "created_at", now),
+      updated_at: Map.get(fields, "updated_at", now)
+    }
+
+    script = Repo.get_by(Script, project_id: project_id, slug: attrs.slug) || %Script{}
+
+    script
+    |> Script.changeset(attrs)
+    |> Repo.insert_or_update!()
+  end
+
+  defp parse_script_kind(kind) when is_atom(kind), do: kind
+  defp parse_script_kind(kind), do: String.to_existing_atom(kind)
+
+  defp list_matching_files(dir, pattern) do
+    if File.dir?(dir) do
+      Path.join(dir, pattern)
+      |> Path.wildcard()
+      |> Enum.sort()
+    else
+      []
+    end
+  end
+
   defp maybe_put(map, _key, nil), do: map
   defp maybe_put(map, key, value), do: Map.put(map, key, value)
 
diff --git a/lib/bds/tags.ex b/lib/bds/tags.ex
index 60416f4..9153c77 100644
--- a/lib/bds/tags.ex
+++ b/lib/bds/tags.ex
@@ -73,6 +73,30 @@ defmodule BDS.Tags do
     end
   end
 
+  def delete_tag(tag_id) do
+    case Repo.get(Tag, tag_id) do
+      nil ->
+        {:error, :not_found}
+
+      tag ->
+        Repo.transaction(fn ->
+          affected_posts = posts_with_tag(tag.project_id, tag.name)
+
+          Enum.each(affected_posts, fn post ->
+            updated_tags = Enum.reject(post.tags || [], &(&1 == tag.name))
+            update_post_tags(post, updated_tags)
+          end)
+
+          Repo.delete!(tag)
+          write_tags_json(tag.project_id)
+        end)
+        |> case do
+          {:ok, _} -> {:ok, :deleted}
+          {:error, reason} -> {:error, reason}
+        end
+    end
+  end
+
   def rename_tag(tag_id, new_name) do
     case Repo.get(Tag, tag_id) do
       nil ->
diff --git a/lib/bds/templates.ex b/lib/bds/templates.ex
index b8250be..5855eda 100644
--- a/lib/bds/templates.ex
+++ b/lib/bds/templates.ex
@@ -4,9 +4,11 @@ defmodule BDS.Templates do
   import Ecto.Query
 
   alias BDS.Frontmatter
+  alias BDS.Posts
   alias BDS.Projects
   alias BDS.Repo
   alias BDS.Slug
+  alias BDS.Tags
   alias BDS.Templates.Template
 
   def create_template(attrs) do
@@ -71,24 +73,58 @@ defmodule BDS.Templates do
           end
 
         content_changed? = has_attr?(attrs, :content) and attr(attrs, :content) != template.content
+        slug_changed? = next_slug != template.slug
         now = System.system_time(:second)
+        next_status = if(template.status == :published and content_changed?, do: :draft, else: template.status)
+        next_file_path = next_template_file_path(template, next_slug)
 
         updates = %{}
         |> maybe_put(:title, attr(attrs, :title))
         |> maybe_put(:kind, attr(attrs, :kind))
         |> maybe_put(:enabled, attr(attrs, :enabled))
         |> maybe_put(:content, attr(attrs, :content))
+        |> Map.put(:file_path, next_file_path)
         |> Map.put(:slug, next_slug)
         |> Map.put(:version, template.version + 1)
         |> Map.put(:updated_at, now)
-        |> maybe_put(:status, if(template.status == :published and content_changed?, do: :draft, else: nil))
+        |> Map.put(:status, next_status)
 
-        template
-        |> Template.changeset(updates)
-        |> Repo.update()
+        Repo.transaction(fn ->
+          updated_template =
+            template
+            |> Template.changeset(updates)
+            |> Repo.update!()
+
+          if slug_changed? do
+            cascade_template_slug_change(template, updated_template, now)
+          end
+
+          if template.file_path not in [nil, ""] and next_file_path != template.file_path do
+            rewrite_template_file(template, updated_template)
+          end
+
+          updated_template
+        end)
+        |> case do
+          {:ok, updated_template} -> {:ok, updated_template}
+          {:error, reason} -> {:error, reason}
+        end
     end
   end
 
+  def rebuild_templates_from_files(project_id) do
+    project = Projects.get_project!(project_id)
+
+    templates =
+      project
+      |> Projects.project_data_dir()
+      |> Path.join("templates")
+      |> list_matching_files("*.liquid")
+      |> Enum.map(&upsert_template_from_file(project_id, project, &1))
+
+    {:ok, templates}
+  end
+
   def delete_template(template_id, opts \\ []) do
     case Repo.get(Template, template_id) do
       nil ->
@@ -154,6 +190,9 @@ defmodule BDS.Templates do
     Path.join(Projects.project_data_dir(project), relative_path)
   end
 
+  defp next_template_file_path(%Template{file_path: ""}, _next_slug), do: ""
+  defp next_template_file_path(%Template{}, next_slug), do: template_file_path(next_slug)
+
   defp serialize_template_file(template, content) do
     Frontmatter.serialize_document(
       [
@@ -195,14 +234,108 @@ defmodule BDS.Templates do
     |> Repo.update_all(set: [post_template_slug: nil, updated_at: now])
 
     Enum.each(affected_posts, fn post ->
-      BDS.Posts.rewrite_published_post(post.id)
+      Posts.rewrite_published_post(post.id)
     end)
 
-    BDS.Tags.sync_tags_json(template.project_id)
+    Tags.sync_tags_json(template.project_id)
 
     :ok
   end
 
+  defp cascade_template_slug_change(original_template, updated_template, updated_at) do
+    affected_posts =
+      Repo.all(
+        from(post in BDS.Posts.Post,
+          where: post.project_id == ^original_template.project_id and post.template_slug == ^original_template.slug
+        )
+      )
+
+    from(post in BDS.Posts.Post,
+      where: post.project_id == ^original_template.project_id and post.template_slug == ^original_template.slug
+    )
+    |> Repo.update_all(set: [template_slug: updated_template.slug, updated_at: updated_at])
+
+    from(tag in BDS.Tags.Tag,
+      where: tag.project_id == ^original_template.project_id and tag.post_template_slug == ^original_template.slug
+    )
+    |> Repo.update_all(set: [post_template_slug: updated_template.slug, updated_at: updated_at])
+
+    Enum.each(affected_posts, fn post ->
+      Posts.rewrite_published_post(post.id)
+    end)
+
+    Tags.sync_tags_json(original_template.project_id)
+  end
+
+  defp rewrite_template_file(original_template, updated_template) do
+    body = published_template_body(original_template)
+    new_full_path = full_file_path(updated_template.project_id, updated_template.file_path)
+    :ok = File.mkdir_p(Path.dirname(new_full_path))
+    :ok = File.write(new_full_path, serialize_template_file(updated_template, body))
+
+    if original_template.file_path != updated_template.file_path do
+      _ = delete_file_if_present(original_template.project_id, original_template.file_path)
+    end
+
+    :ok
+  end
+
+  defp published_template_body(%Template{content: content}) when is_binary(content), do: content
+
+  defp published_template_body(template) do
+    case File.read(full_file_path(template.project_id, template.file_path)) do
+      {:ok, contents} ->
+        case Frontmatter.parse_document(contents) do
+          {:ok, %{body: body}} -> body
+          {:error, _reason} -> ""
+        end
+
+      {:error, _reason} ->
+        ""
+    end
+  end
+
+  defp upsert_template_from_file(project_id, project, path) do
+    contents = File.read!(path)
+    {:ok, %{fields: fields}} = Frontmatter.parse_document(contents)
+    relative_path = Path.relative_to(path, Projects.project_data_dir(project))
+    now = System.system_time(:second)
+
+    attrs = %{
+      id: Map.get(fields, "id") || Ecto.UUID.generate(),
+      project_id: project_id,
+      slug: Map.fetch!(fields, "slug"),
+      title: Map.get(fields, "title") || "",
+      kind: parse_template_kind(Map.fetch!(fields, "kind")),
+      enabled: Map.get(fields, "enabled", true),
+      version: Map.get(fields, "version", 1),
+      file_path: relative_path,
+      status: :published,
+      content: nil,
+      created_at: Map.get(fields, "created_at", now),
+      updated_at: Map.get(fields, "updated_at", now)
+    }
+
+    template = Repo.get_by(Template, project_id: project_id, slug: attrs.slug) || %Template{}
+
+    template
+    |> Template.changeset(attrs)
+    |> Repo.insert_or_update!()
+  end
+
+  defp parse_template_kind(kind) when is_atom(kind), do: kind
+  defp parse_template_kind(kind), do: String.to_existing_atom(kind)
+
+  defp list_matching_files(dir, pattern) do
+    if File.dir?(dir) do
+      Path.join(dir, pattern)
+      |> Path.wildcard()
+      |> Enum.sort()
+    else
+      []
+    end
+  end
+
   defp delete_file_if_present(_project_id, file_path) when file_path in [nil, ""], do: :ok
 
   defp delete_file_if_present(project_id, file_path) do
diff --git a/test/bds/scripts_test.exs b/test/bds/scripts_test.exs
index 7c11372..8d1ea50 100644
--- a/test/bds/scripts_test.exs
+++ b/test/bds/scripts_test.exs
@@ -115,4 +115,48 @@ defmodule BDS.ScriptsTest do
     assert Repo.get(Script, published.id) == nil
     refute File.exists?(Path.join(temp_dir, published.file_path))
   end
+
+  test "rebuild_scripts_from_files recreates published scripts from disk", %{project: project, temp_dir: temp_dir} do
+    script_dir = Path.join(temp_dir, "scripts")
+    File.mkdir_p!(script_dir)
+
+    file_path = Path.join(script_dir, "recovered.lua")
+
+    File.write!(
+      file_path,
+      [
+        "---",
+        "id: script-from-file",
+        "slug: recovered",
+        "title: Recovered Script",
+        "kind: utility",
+        "entrypoint: main",
+        "enabled: true",
+        "version: 4",
+        "created_at: 301",
+        "updated_at: 404",
+        "---",
+        "function main() return 'restored' end",
+        ""
+      ]
+      |> Enum.join("\n")
+    )
+
+    assert {:ok, scripts} = BDS.Scripts.rebuild_scripts_from_files(project.id)
+    assert length(scripts) == 1
+
+    [script] = Repo.all(Script)
+    assert script.id == "script-from-file"
+    assert script.slug == "recovered"
+    assert script.title == "Recovered Script"
+    assert script.kind == :utility
+    assert script.entrypoint == "main"
+    assert script.enabled == true
+    assert script.version == 4
+    assert script.status == :published
+    assert script.file_path == "scripts/recovered.lua"
+    assert script.content == nil
+    assert script.created_at == 301
+    assert script.updated_at == 404
+  end
 end
diff --git a/test/bds/tags_test.exs b/test/bds/tags_test.exs
index 961dd4b..11ac45b 100644
--- a/test/bds/tags_test.exs
+++ b/test/bds/tags_test.exs
@@ -115,6 +115,36 @@ defmodule BDS.TagsTest do
     assert %{"tags" => [%{"name" => "Gamma"}]} = Jason.decode!(File.read!(tags_path))
   end
 
+  test "delete_tag removes the tag from posts, rewrites published files, deletes the row, and refreshes tags.json", %{project: project, temp_dir: temp_dir} do
+    assert {:ok, doomed} = BDS.Tags.create_tag(%{project_id: project.id, name: "Alpha"})
+    assert {:ok, _other} = BDS.Tags.create_tag(%{project_id: project.id, name: "Beta"})
+
+    assert {:ok, post} =
+             BDS.Posts.create_post(%{
+               project_id: project.id,
+               title: "Delete Me",
+               content: "Body",
+               tags: ["Alpha", "Beta"]
+             })
+
+    assert {:ok, published_post} = BDS.Posts.publish_post(post.id)
+
+    assert {:ok, :deleted} = BDS.Tags.delete_tag(doomed.id)
+
+    reloaded_post = Repo.get!(Post, published_post.id)
+    assert reloaded_post.tags == ["Beta"]
+    assert Repo.get(BDS.Tags.Tag, doomed.id) == nil
+
+    post_path = Path.join(temp_dir, reloaded_post.file_path)
+    contents = File.read!(post_path)
+    refute contents =~ "  - Alpha\n"
+    assert contents =~ "tags:\n  - Beta\n"
+    assert contents =~ "\n---\nBody\n"
+
+    tags_path = Path.join([temp_dir, "meta", "tags.json"])
+    assert %{"tags" => [%{"name" => "Beta"}]} = Jason.decode!(File.read!(tags_path))
+  end
+
   defp errors_on(changeset) do
     Ecto.Changeset.traverse_errors(changeset, fn {message, opts} ->
       Regex.replace(~r"%{(\w+)}", message, fn _, key ->
diff --git a/test/bds/templates_test.exs b/test/bds/templates_test.exs
index 824a8f3..77da74b 100644
--- a/test/bds/templates_test.exs
+++ b/test/bds/templates_test.exs
@@ -142,4 +142,105 @@ defmodule BDS.TemplatesTest do
     tags_path = Path.join([temp_dir, "meta", "tags.json"])
     assert %{"tags" => [%{"name" => "Feature"}]} = Jason.decode!(File.read!(tags_path))
   end
+
+  test "update_template cascades slug changes to posts and tags and renames the published file", %{project: project, temp_dir: temp_dir} do
+    assert {:ok, template} =
+             BDS.Templates.create_template(%{
+               project_id: project.id,
+               title: "Article View",
+               kind: :post,
+               content: "<article>{{ content }}</article>"
+             })
+
+    assert {:ok, published} = BDS.Templates.publish_template(template.id)
+
+    assert {:ok, post} =
+             BDS.Posts.create_post(%{
+               project_id: project.id,
+               title: "Uses Template",
+               content: "Body",
+               template_slug: published.slug
+             })
+
+    assert {:ok, published_post} = BDS.Posts.publish_post(post.id)
+
+    assert {:ok, _tag} =
+             BDS.Tags.create_tag(%{
+               project_id: project.id,
+               name: "Feature",
+               post_template_slug: published.slug
+             })
+
+    old_template_path = Path.join(temp_dir, published.file_path)
+    assert File.exists?(old_template_path)
+
+    assert {:ok, updated} = BDS.Templates.update_template(published.id, %{slug: "feature-view"})
+
+    assert updated.slug == "feature-view"
+    assert updated.file_path == "templates/feature-view.liquid"
+
+    reloaded_post = Repo.get!(Post, published_post.id)
+    assert reloaded_post.template_slug == "feature-view"
+
+    reloaded_tag = Repo.get_by!(Tag, project_id: project.id, name: "Feature")
+    assert reloaded_tag.post_template_slug == "feature-view"
+
+    refute File.exists?(old_template_path)
+    new_template_path = Path.join(temp_dir, updated.file_path)
+    assert File.exists?(new_template_path)
+
+    template_contents = File.read!(new_template_path)
+    assert template_contents =~ "slug: feature-view\n"
+    assert template_contents =~ "\n---\n<article>{{ content }}</article>\n"
+
+    post_contents = File.read!(Path.join(temp_dir, reloaded_post.file_path))
+    assert post_contents =~ "template_slug: feature-view\n"
+    assert post_contents =~ "\n---\nBody\n"
+
+    tags_path = Path.join([temp_dir, "meta", "tags.json"])
+    assert %{"tags" => [%{"name" => "Feature", "post_template_slug" => "feature-view"}]} =
+             Jason.decode!(File.read!(tags_path))
+  end
+
+  test "rebuild_templates_from_files recreates published templates from disk", %{project: project, temp_dir: temp_dir} do
+    template_dir = Path.join(temp_dir, "templates")
+    File.mkdir_p!(template_dir)
+
+    file_path = Path.join(template_dir, "recovered-view.liquid")
+
+    File.write!(
+      file_path,
+      [
+        "---",
+        "id: template-from-file",
+        "slug: recovered-view",
+        "title: Recovered View",
+        "kind: list",
+        "enabled: true",
+        "version: 3",
+        "created_at: 101",
+        "updated_at: 202",
+        "---",
+        "<section>Recovered</section>",
+        ""
+      ]
+      |> Enum.join("\n")
+    )
+
+    assert {:ok, templates} = BDS.Templates.rebuild_templates_from_files(project.id)
+    assert length(templates) == 1
+
+    [template] = Repo.all(BDS.Templates.Template)
+    assert template.id == "template-from-file"
+    assert template.slug == "recovered-view"
+    assert template.title == "Recovered View"
+    assert template.kind == :list
+    assert template.enabled == true
+    assert template.version == 3
+    assert template.status == :published
+    assert template.file_path == "templates/recovered-view.liquid"
+    assert template.content == nil
+    assert template.created_at == 101
+    assert template.updated_at == 202
+  end
 end