diff --git a/lib/bds/desktop/shell_live/settings_editor/style_editor.ex b/lib/bds/desktop/shell_live/settings_editor/style_editor.ex
index 458ce8f..69bb18e 100644
--- a/lib/bds/desktop/shell_live/settings_editor/style_editor.ex
+++ b/lib/bds/desktop/shell_live/settings_editor/style_editor.ex
@@ -4,6 +4,7 @@ defmodule BDS.Desktop.ShellLive.SettingsEditor.StyleEditor do
   use Phoenix.Component
 
   alias BDS.Metadata
+  alias BDS.Preview
   use Gettext, backend: BDS.Gettext
 
   @themes [
@@ -42,7 +43,8 @@ defmodule BDS.Desktop.ShellLive.SettingsEditor.StyleEditor do
       applied_theme: current_theme(assigns),
       preview_mode: preview_mode,
       preview_url:
-        "http://127.0.0.1:4123/__style-preview?theme=#{selected_theme}&mode=#{preview_mode}"
+        Preview.base_url() <>
+          "/__style-preview?theme=#{selected_theme}&mode=#{preview_mode}"
     }
   end
 
diff --git a/lib/bds/preview.ex b/lib/bds/preview.ex
index 474867b..fb836bb 100644
--- a/lib/bds/preview.ex
+++ b/lib/bds/preview.ex
@@ -12,12 +12,14 @@ defmodule BDS.Preview do
   alias BDS.Rendering.TemplateSelection
 
   @host "127.0.0.1"
-  @port 4123
+  @preferred_port 4123
   @server_table __MODULE__.ServerTable
 
   # Max time to wait for inflight requests to finish during graceful shutdown
   # before remaining request tasks are forcibly terminated.
   @drain_timeout 5_000
+  @listen_retry_attempts 10
+  @listen_retry_delay_ms 50
 
   def start_link(_opts) do
     GenServer.start_link(__MODULE__, %{}, name: __MODULE__)
@@ -41,7 +43,17 @@ defmodule BDS.Preview do
     )
   end
 
-  def base_url, do: "http://#{@host}:#{@port}"
+  def base_url do
+    case :ets.whereis(@server_table) do
+      :undefined -> "http://#{@host}:#{@preferred_port}"
+
+      _table ->
+        case :ets.lookup(@server_table, :current) do
+          [{:current, %{host: host, port: port}}] -> "http://#{host}:#{port}"
+          _other -> "http://#{@host}:#{@preferred_port}"
+        end
+    end
+  end
 
   def stop_preview(project_id) when is_binary(project_id) do
     GenServer.call(__MODULE__, {:stop_preview, project_id})
@@ -501,14 +513,7 @@ defmodule BDS.Preview do
     state = stop_current_server(state)
     maybe_allow_repo(owner_pid)
 
-    {:ok, listener} =
-      :gen_tcp.listen(@port, [
-        :binary,
-        packet: :raw,
-        active: false,
-        reuseaddr: true,
-        ip: {127, 0, 0, 1}
-      ])
+    {:ok, listener, port} = listen_with_retry(@listen_retry_attempts)
 
     acceptor_pid = spawn_link(fn -> accept_loop(listener, project_id, owner_pid) end)
 
@@ -516,7 +521,7 @@ defmodule BDS.Preview do
       project_id: project_id,
       data_dir: data_dir,
       host: @host,
-      port: @port,
+      port: port,
       is_running: true,
       owner_pid: owner_pid,
       listener: listener,
@@ -528,6 +533,40 @@ defmodule BDS.Preview do
     {{:ok, public_server(server)}, %{state | current: server}}
   end
 
+  defp listen_with_retry(attempts_left) when attempts_left > 0 do
+    case listen_on_port(@preferred_port) do
+      {:ok, listener, port} ->
+        {:ok, listener, port}
+
+      {:error, :eaddrinuse} when attempts_left > 1 ->
+        Process.sleep(@listen_retry_delay_ms)
+        listen_with_retry(attempts_left - 1)
+
+      {:error, :eaddrinuse} ->
+        listen_on_port(0)
+
+      {:error, reason} ->
+        {:error, reason}
+    end
+  end
+
+  defp listen_on_port(port) do
+    case :gen_tcp.listen(port, [
+           :binary,
+           packet: :raw,
+           active: false,
+           reuseaddr: true,
+           ip: {127, 0, 0, 1}
+         ]) do
+      {:ok, listener} ->
+        {:ok, {_host, actual_port}} = :inet.sockname(listener)
+        {:ok, listener, actual_port}
+
+      {:error, reason} ->
+        {:error, reason}
+    end
+  end
+
   defp run_tracked_request(fun) when is_function(fun, 0) do
     owner_pid = self()
 
diff --git a/lib/bds/projects.ex b/lib/bds/projects.ex
index 36b8c52..a87d664 100644
--- a/lib/bds/projects.ex
+++ b/lib/bds/projects.ex
@@ -12,6 +12,8 @@ defmodule BDS.Projects do
 
   @default_project_id "default"
   @default_project_name "My Blog"
+  @create_project_retry_attempts 5
+  @create_project_retry_delay_ms 50
 
   @typedoc "An attribute map that may use atom or string keys."
   @type attrs :: %{optional(atom()) => term(), optional(String.t()) => term()}
@@ -152,22 +154,24 @@ defmodule BDS.Projects do
     name = attr(attrs, :name) || ""
     slug = unique_slug(attr(attrs, :slug) || Slug.slugify(name))
 
-    Repo.transaction(fn ->
-      project =
-        %Project{}
-        |> Project.changeset(%{
-          id: Ecto.UUID.generate(),
-          name: name,
-          slug: slug,
-          description: attr(attrs, :description),
-          data_path: attr(attrs, :data_path),
-          created_at: now,
-          updated_at: now,
-          is_active: false
-        })
-        |> Repo.insert!()
+    retry_create_project(fn ->
+      Repo.transaction(fn ->
+        project =
+          %Project{}
+          |> Project.changeset(%{
+            id: Ecto.UUID.generate(),
+            name: name,
+            slug: slug,
+            description: attr(attrs, :description),
+            data_path: attr(attrs, :data_path),
+            created_at: now,
+            updated_at: now,
+            is_active: false
+          })
+          |> Repo.insert!()
 
-      project
+        project
+      end)
     end)
     |> case do
       {:ok, project} ->
@@ -182,6 +186,22 @@ defmodule BDS.Projects do
     end
   end
 
+  defp retry_create_project(fun, attempts_left \\ @create_project_retry_attempts)
+
+  defp retry_create_project(fun, attempts_left) when attempts_left > 1 do
+    fun.()
+  rescue
+    error in [Exqlite.Error] ->
+      if String.contains?(Exception.message(error), "Database busy") do
+        Process.sleep(@create_project_retry_delay_ms)
+        retry_create_project(fun, attempts_left - 1)
+      else
+        reraise error, __STACKTRACE__
+      end
+  end
+
+  defp retry_create_project(fun, _attempts_left), do: fun.()
+
   @spec set_active_project(String.t()) :: {:ok, Project.t()} | {:error, :not_found | term()}
   def set_active_project(project_id) do
     case Repo.get(Project, project_id) do
diff --git a/test/bds/ai/chat_sandbox_cleanup_test.exs b/test/bds/ai/chat_sandbox_cleanup_test.exs
index 86928e7..74b1f99 100644
--- a/test/bds/ai/chat_sandbox_cleanup_test.exs
+++ b/test/bds/ai/chat_sandbox_cleanup_test.exs
@@ -20,6 +20,8 @@ defmodule BDS.AI.ChatSandboxCleanupTest do
 
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
+    Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
     :ok
   end
 
diff --git a/test/bds/blogmark_test.exs b/test/bds/blogmark_test.exs
index 3f24f1b..a48ceaa 100644
--- a/test/bds/blogmark_test.exs
+++ b/test/bds/blogmark_test.exs
@@ -7,6 +7,7 @@ defmodule BDS.BlogmarkTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     temp_dir =
       Path.join(System.tmp_dir!(), "bds-blogmark-#{System.unique_integer([:positive])}")
diff --git a/test/bds/csm007_reload_shell_test.exs b/test/bds/csm007_reload_shell_test.exs
index 17dacf6..dabf985 100644
--- a/test/bds/csm007_reload_shell_test.exs
+++ b/test/bds/csm007_reload_shell_test.exs
@@ -9,6 +9,7 @@ defmodule BDS.CSM007ReloadShellTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     temp_dir =
       Path.join(System.tmp_dir!(), "bds-csm007-#{System.unique_integer([:positive])}")
diff --git a/test/bds/csm008_render_path_test.exs b/test/bds/csm008_render_path_test.exs
index 736d98d..0115121 100644
--- a/test/bds/csm008_render_path_test.exs
+++ b/test/bds/csm008_render_path_test.exs
@@ -9,6 +9,7 @@ defmodule BDS.CSM008RenderPathTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     temp_dir =
       Path.join(System.tmp_dir!(), "bds-csm008-#{System.unique_integer([:positive])}")
diff --git a/test/bds/csm011_url_state_test.exs b/test/bds/csm011_url_state_test.exs
index 1851c42..5183c4c 100644
--- a/test/bds/csm011_url_state_test.exs
+++ b/test/bds/csm011_url_state_test.exs
@@ -9,6 +9,7 @@ defmodule BDS.CSM011UrlStateTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     prev = System.get_env("BDS_DESKTOP_AUTOMATION")
     System.put_env("BDS_DESKTOP_AUTOMATION", "1")
diff --git a/test/bds/csm012_file_picker_async_test.exs b/test/bds/csm012_file_picker_async_test.exs
index 61e4c45..51c1820 100644
--- a/test/bds/csm012_file_picker_async_test.exs
+++ b/test/bds/csm012_file_picker_async_test.exs
@@ -9,6 +9,7 @@ defmodule BDS.CSM012FilePickerAsyncTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     prev = System.get_env("BDS_DESKTOP_AUTOMATION")
     System.put_env("BDS_DESKTOP_AUTOMATION", "1")
diff --git a/test/bds/desktop/import_shell_live_test.exs b/test/bds/desktop/import_shell_live_test.exs
index 9579dac..8a944f0 100644
--- a/test/bds/desktop/import_shell_live_test.exs
+++ b/test/bds/desktop/import_shell_live_test.exs
@@ -12,6 +12,7 @@ defmodule BDS.Desktop.ImportShellLiveTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     Enum.each(BDS.Tasks.list_running_tasks(), fn task ->
       BDS.Tasks.cancel_task(task.id)
diff --git a/test/bds/desktop/misc_editor_test.exs b/test/bds/desktop/misc_editor_test.exs
index 1ee0ae9..ab3fb10 100644
--- a/test/bds/desktop/misc_editor_test.exs
+++ b/test/bds/desktop/misc_editor_test.exs
@@ -11,6 +11,7 @@ defmodule BDS.Desktop.MiscEditorTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     temp_dir =
       Path.join(System.tmp_dir!(), "bds-misc-editor-test-#{System.unique_integer([:positive])}")
diff --git a/test/bds/desktop/shell_commands_test.exs b/test/bds/desktop/shell_commands_test.exs
index ae8eeb4..c855263 100644
--- a/test/bds/desktop/shell_commands_test.exs
+++ b/test/bds/desktop/shell_commands_test.exs
@@ -87,8 +87,19 @@ defmodule BDS.Desktop.ShellCommandsTest do
   end
 
   setup do
+    if :ets.whereis(BDS.Preview.ServerTable) != :undefined do
+      case :ets.lookup(BDS.Preview.ServerTable, :current) do
+        [{:current, %{project_id: project_id}}] ->
+          _ = BDS.Preview.stop_preview(project_id)
+
+        _other ->
+          :ok
+      end
+    end
+
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
     :ok = Ecto.Adapters.SQL.Sandbox.allow(BDS.Repo, self(), Process.whereis(BDS.Preview))
     :ok = Ecto.Adapters.SQL.Sandbox.allow(BDS.Repo, self(), Process.whereis(BDS.Publishing))
     :ok = BDS.Tasks.clear_finished()
@@ -117,7 +128,7 @@ defmodule BDS.Desktop.ShellCommandsTest do
 
     assert result.kind == "open_url"
     assert result.action == "open_in_browser"
-    assert result.url == "http://127.0.0.1:4123/"
+    assert result.url == BDS.Preview.base_url() <> "/"
     assert result.project_id == project.id
   end
 
diff --git a/test/bds/desktop/shell_live_test.exs b/test/bds/desktop/shell_live_test.exs
index 421d01f..db365b9 100644
--- a/test/bds/desktop/shell_live_test.exs
+++ b/test/bds/desktop/shell_live_test.exs
@@ -640,8 +640,29 @@ defmodule BDS.Desktop.ShellLiveTest do
   end
 
   setup do
+    if :ets.whereis(BDS.Preview.ServerTable) != :undefined do
+      case :ets.lookup(BDS.Preview.ServerTable, :current) do
+        [{:current, %{project_id: project_id}}] ->
+          _ = BDS.Preview.stop_preview(project_id)
+
+        _other ->
+          :ok
+      end
+    end
+
+    if :ets.whereis(BDS.Preview.ServerTable) != :undefined do
+      case :ets.lookup(BDS.Preview.ServerTable, :current) do
+        [{:current, %{project_id: project_id}}] ->
+          _ = BDS.Preview.stop_preview(project_id)
+
+        _other ->
+          :ok
+      end
+    end
+
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     Enum.each(BDS.Tasks.list_running_tasks(), fn task ->
       BDS.Tasks.cancel_task(task.id)
@@ -661,7 +682,8 @@ defmodule BDS.Desktop.ShellLiveTest do
       DynamicSupervisor.terminate_child(BDS.Tasks.TaskSupervisor, pid)
     end
 
-    Process.sleep(100)
+    wait_for_supervisor_clear(BDS.TCP.TaskSupervisor)
+    wait_for_supervisor_clear(BDS.Tasks.TaskSupervisor)
 
     temp_dir =
       Path.join(System.tmp_dir!(), "bds-shell-live-#{System.unique_integer([:positive])}")
@@ -700,6 +722,21 @@ defmodule BDS.Desktop.ShellLiveTest do
     %{project: project, temp_dir: temp_dir}
   end
 
+  defp wait_for_supervisor_clear(supervisor, attempts \\ 50)
+
+  defp wait_for_supervisor_clear(_supervisor, 0), do: :ok
+
+  defp wait_for_supervisor_clear(supervisor, attempts) do
+    case DynamicSupervisor.which_children(supervisor) do
+      [] ->
+        :ok
+
+      _children ->
+        Process.sleep(10)
+        wait_for_supervisor_clear(supervisor, attempts - 1)
+    end
+  end
+
   test "sidebar headers expose old-app create actions for posts, media, scripts, templates, chat, and imports" do
     {:ok, view, html} = live_isolated(build_conn(), BDS.Desktop.ShellLive)
 
diff --git a/test/bds/desktop/style_editor_test.exs b/test/bds/desktop/style_editor_test.exs
index f632657..f6fe263 100644
--- a/test/bds/desktop/style_editor_test.exs
+++ b/test/bds/desktop/style_editor_test.exs
@@ -72,7 +72,7 @@ defmodule BDS.Desktop.ShellLive.SettingsEditor.StyleEditorTest do
       result = StyleEditor.build_style(assigns)
       assert result.preview_url =~ "theme=default"
       assert result.preview_url =~ "mode=auto"
-      assert result.preview_url =~ "127.0.0.1:4123/__style-preview"
+      assert result.preview_url =~ BDS.Preview.base_url() <> "/__style-preview"
     end
 
     test "preview_url reflects selected_theme", %{project: project} do
diff --git a/test/bds/desktop/tag_editor_live_test.exs b/test/bds/desktop/tag_editor_live_test.exs
index 9e8adc6..ea963ec 100644
--- a/test/bds/desktop/tag_editor_live_test.exs
+++ b/test/bds/desktop/tag_editor_live_test.exs
@@ -12,6 +12,7 @@ defmodule BDS.Desktop.TagEditorLiveTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     Enum.each(BDS.Tasks.list_running_tasks(), fn task ->
       BDS.Tasks.cancel_task(task.id)
diff --git a/test/bds/desktop/template_editor_live_test.exs b/test/bds/desktop/template_editor_live_test.exs
index e58e41e..d7aadc8 100644
--- a/test/bds/desktop/template_editor_live_test.exs
+++ b/test/bds/desktop/template_editor_live_test.exs
@@ -15,6 +15,7 @@ defmodule BDS.Desktop.TemplateEditorLiveTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     Enum.each(BDS.Tasks.list_running_tasks(), fn task ->
       BDS.Tasks.cancel_task(task.id)
diff --git a/test/bds/post_translations_test.exs b/test/bds/post_translations_test.exs
index 3ede77c..e5885c5 100644
--- a/test/bds/post_translations_test.exs
+++ b/test/bds/post_translations_test.exs
@@ -53,6 +53,7 @@ defmodule BDS.PostTranslationsTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
     :ok = BDS.Tasks.clear_finished()
 
     temp_dir =
diff --git a/test/bds/preview_test.exs b/test/bds/preview_test.exs
index e9da615..55ca47d 100644
--- a/test/bds/preview_test.exs
+++ b/test/bds/preview_test.exs
@@ -21,15 +21,46 @@ defmodule BDS.PreviewTest do
   alias BDS.Posts
 
   setup do
+    reset_preview_process()
+
+    for {_, pid, _, _} <- DynamicSupervisor.which_children(BDS.TCP.TaskSupervisor) do
+      DynamicSupervisor.terminate_child(BDS.TCP.TaskSupervisor, pid)
+    end
+
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
+    Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
+
     temp_dir = Path.join(System.tmp_dir!(), "bds-preview-#{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: "Preview", data_path: temp_dir})
+
+    on_exit(fn ->
+      _ = BDS.Preview.stop_preview(project.id)
+    end)
+
     %{project: project, temp_dir: temp_dir}
   end
 
+  defp reset_preview_process do
+    case :ets.whereis(BDS.Preview.ServerTable) do
+      :undefined ->
+        :ok
+
+      _table ->
+        case :ets.lookup(BDS.Preview.ServerTable, :current) do
+          [{:current, %{project_id: project_id}}] ->
+            _ = BDS.Preview.stop_preview(project_id)
+            :ok
+
+          _other ->
+            :ok
+        end
+    end
+  end
+
   test "start_preview binds localhost and request resolves generated routes, assets, media, and draft previews",
        %{project: project, temp_dir: temp_dir} do
     assert {:ok, _metadata} =
@@ -77,8 +108,9 @@ defmodule BDS.PreviewTest do
 
     assert {:ok, server} = BDS.Preview.start_preview(project.id)
     assert server.host == "127.0.0.1"
-    assert server.port == 4123
+    assert server.port > 0
     assert server.is_running == true
+    assert BDS.Preview.base_url() == "http://127.0.0.1:#{server.port}"
 
     assert {:ok, %{body: home_html, content_type: "text/html"}} =
              BDS.Preview.request(project.id, "/")
diff --git a/test/bds/real_blog_rebuild_diagnostic_test.exs b/test/bds/real_blog_rebuild_diagnostic_test.exs
index 03e5998..e3f7f4c 100644
--- a/test/bds/real_blog_rebuild_diagnostic_test.exs
+++ b/test/bds/real_blog_rebuild_diagnostic_test.exs
@@ -8,6 +8,7 @@ defmodule BDS.RealBlogRebuildDiagnosticTest do
     setup do
       :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo, ownership_timeout: 600_000)
       Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+      on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
       now = BDS.Persistence.now_ms()
       unique = Integer.to_string(System.unique_integer([:positive]))
diff --git a/test/bds/scripting/api_test.exs b/test/bds/scripting/api_test.exs
index 806c69a..300c067 100644
--- a/test/bds/scripting/api_test.exs
+++ b/test/bds/scripting/api_test.exs
@@ -36,6 +36,7 @@ defmodule BDS.Scripting.ApiTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     temp_dir =
       Path.join(System.tmp_dir!(), "bds-scripting-api-#{System.unique_integer([:positive])}")
@@ -45,6 +46,10 @@ defmodule BDS.Scripting.ApiTest do
 
     {:ok, project} = BDS.Projects.create_project(%{name: "Scripting API", data_path: temp_dir})
 
+    on_exit(fn ->
+      _ = BDS.Preview.stop_preview(project.id)
+    end)
+
     %{project: project}
   end
 
diff --git a/test/bds/scripts/transforms_test.exs b/test/bds/scripts/transforms_test.exs
index c3b2bb4..70596dd 100644
--- a/test/bds/scripts/transforms_test.exs
+++ b/test/bds/scripts/transforms_test.exs
@@ -7,6 +7,7 @@ defmodule BDS.Scripts.TransformsTest do
   setup do
     :ok = Ecto.Adapters.SQL.Sandbox.checkout(BDS.Repo)
     Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, {:shared, self()})
+    on_exit(fn -> Ecto.Adapters.SQL.Sandbox.mode(BDS.Repo, :manual) end)
 
     temp_dir =
       Path.join(System.tmp_dir!(), "bds-transforms-#{System.unique_integer([:positive])}")
diff --git a/test/bds/templates_test.exs b/test/bds/templates_test.exs
index 5abb187..5e6e9c2 100644
--- a/test/bds/templates_test.exs
+++ b/test/bds/templates_test.exs
@@ -240,7 +240,7 @@ defmodule BDS.TemplatesTest do
              Jason.decode!(File.read!(tags_path))
   end
 
-  test "update_template keeps committed database changes when renaming the published file fails",
+  test "update_template keeps committed database changes when rewriting the published file fails",
        %{project: project, temp_dir: temp_dir} do
     assert {:ok, template} =
              BDS.Templates.create_template(%{
@@ -269,8 +269,9 @@ defmodule BDS.TemplatesTest do
                post_template_slug: published.slug
              })
 
-    blocked_path = Path.join([temp_dir, "templates", "feature-view.liquid.tmp"])
-    File.mkdir_p!(blocked_path)
+    published_template_path = Path.join(temp_dir, published.file_path)
+    File.rm!(published_template_path)
+    File.mkdir_p!(published_template_path)
 
     assert {:error, _reason} =
              BDS.Templates.update_template(published.id, %{slug: "feature-view"})