diff --git a/lib/bds/desktop/shell_data.ex b/lib/bds/desktop/shell_data.ex
index f1dd64c..7f4b420 100644
--- a/lib/bds/desktop/shell_data.ex
+++ b/lib/bds/desktop/shell_data.ex
@@ -1,6 +1,7 @@
 defmodule BDS.Desktop.ShellData do
   @moduledoc false
 
+  alias BDS.Git
   alias BDS.I18n
   alias BDS.Projects
   alias BDS.UI.Dashboard
@@ -100,6 +101,30 @@ defmodule BDS.Desktop.ShellData do
     )
   end
 
+  def git_badge_count(project_id, opts \\ [])
+
+  def git_badge_count(nil, _opts), do: 0
+  def git_badge_count("default", _opts), do: 0
+
+  def git_badge_count(project_id, opts) when is_binary(project_id) do
+    provider = Keyword.get(opts, :provider, git_remote_state_provider())
+
+    try do
+      case provider.(project_id, []) do
+        {:ok, %{behind: behind}} when is_integer(behind) and behind > 0 -> behind
+        {:ok, %{behind: behind}} when is_binary(behind) -> parse_positive_count(behind)
+        _other -> 0
+      end
+    rescue
+      error in [DBConnection.OwnershipError, Exqlite.Error] ->
+        if match?(%Exqlite.Error{}, error) and not String.contains?(Exception.message(error), "no such table") do
+          reraise error, __STACKTRACE__
+        end
+
+        0
+    end
+  end
+
   def panel_tabs(workbench) do
     [:tasks, :output]
     |> maybe_add_panel_tab(workbench.editor_route, :post_links)
@@ -108,6 +133,17 @@ defmodule BDS.Desktop.ShellData do
     |> Enum.uniq()
   end
 
+  defp git_remote_state_provider do
+    Application.get_env(:bds, :git_remote_state_provider, &Git.remote_state/2)
+  end
+
+  defp parse_positive_count(value) do
+    case Integer.parse(value) do
+      {count, _rest} when count > 0 -> count
+      _other -> 0
+    end
+  end
+
   def activity_icon(id) do
     case to_string(id) do
       "posts" -> ~s(<svg width="24" height="24" viewBox="0 0 24 24" fill="currentColor"><path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8l-6-6zM6 20V4h7v5h5v11H6z"></path><path d="M8 12h8v2H8zm0 4h8v2H8z"></path></svg>)
diff --git a/lib/bds/desktop/shell_live.ex b/lib/bds/desktop/shell_live.ex
index 7fa13eb..122dd49 100644
--- a/lib/bds/desktop/shell_live.ex
+++ b/lib/bds/desktop/shell_live.ex
@@ -394,11 +394,12 @@ defmodule BDS.Desktop.ShellLive do
   defp reload_shell(socket, workbench) do
     projects = ShellData.project_snapshot()
     dashboard = ShellData.dashboard(projects.active_project_id)
+    git_badge_count = ShellData.git_badge_count(projects.active_project_id)
     active_view_id = Atom.to_string(workbench.active_view)
     sidebar_data = ShellData.sidebar_view(projects.active_project_id, active_view_id, current_sidebar_filters(socket, active_view_id))
     sidebar_data = merge_sidebar_ui_state(socket, active_view_id, sidebar_data)
     task_status = BDS.Tasks.status_snapshot()
-    activity_buttons = Workbench.activity_buttons(workbench, 0)
+    activity_buttons = Workbench.activity_buttons(workbench, git_badge_count)
     page_language = socket.assigns[:page_language] || ShellData.ui_language()
     offline_mode = Map.get(socket.assigns, :offline_mode, true)
 
diff --git a/lib/bds/desktop/shell_live/index.html.heex b/lib/bds/desktop/shell_live/index.html.heex
index 5c50e0f..ffb8659 100644
--- a/lib/bds/desktop/shell_live/index.html.heex
+++ b/lib/bds/desktop/shell_live/index.html.heex
@@ -112,6 +112,9 @@
             aria-label={activity_label(button.label)}
           >
             <%= raw(ShellData.activity_icon(button.id)) %>
+            <%= if button.badge do %>
+              <span class="activity-bar-badge"><%= button.badge.display %></span>
+            <% end %>
           </button>
         <% end %>
       </div>
@@ -129,6 +132,9 @@
             aria-label={activity_label(button.label)}
           >
             <%= raw(ShellData.activity_icon(button.id)) %>
+            <%= if button.badge do %>
+              <span class="activity-bar-badge"><%= button.badge.display %></span>
+            <% end %>
           </button>
         <% end %>
       </div>
diff --git a/lib/bds/git.ex b/lib/bds/git.ex
index 01c9619..b888453 100644
--- a/lib/bds/git.ex
+++ b/lib/bds/git.ex
@@ -171,6 +171,26 @@ defmodule BDS.Git do
     end
   end
 
+  def remote_state(project_id, opts \\ []) when is_binary(project_id) and is_list(opts) do
+    with {:ok, project_dir} <- project_dir(project_id),
+         {:ok, local_branch} <- current_branch(project_dir, opts) do
+      case upstream_branch(project_dir, opts) do
+        {:ok, nil} ->
+          {:ok, %{local_branch: local_branch, upstream_branch: nil, has_upstream: false, ahead: 0, behind: 0}}
+
+        {:ok, upstream_branch} ->
+          {:ok,
+           %{
+             local_branch: local_branch,
+             upstream_branch: upstream_branch,
+             has_upstream: true,
+             ahead: revision_count(project_dir, "#{upstream_branch}..HEAD", opts),
+             behind: revision_count(project_dir, "HEAD..#{upstream_branch}", opts)
+           }}
+      end
+    end
+  end
+
   defp project_dir(project_id) do
     case Projects.get_project(project_id) do
       nil -> {:error, :not_found}
@@ -274,6 +294,13 @@ defmodule BDS.Git do
     ]
   end
 
+  defp upstream_branch(project_dir, opts) do
+    case run_git(project_dir, ["rev-parse", "--abbrev-ref", "--symbolic-full-name", "@{upstream}"], opts) do
+      {:ok, output} -> {:ok, blank_to_nil(output)}
+      {:error, {:git_failed, _message}} -> {:ok, nil}
+    end
+  end
+
   defp parse_status(output) do
     output
     |> String.split("\n", trim: true)
@@ -334,6 +361,20 @@ defmodule BDS.Git do
     end
   end
 
+  defp revision_count(project_dir, revision_range, opts) do
+    case run_git(project_dir, ["rev-list", "--count", revision_range], opts) do
+      {:ok, output} -> parse_count(output)
+      {:error, {:git_failed, _message}} -> 0
+    end
+  end
+
+  defp parse_count(value) do
+    case Integer.parse(to_string(value || "")) do
+      {count, _rest} -> count
+      :error -> 0
+    end
+  end
+
   defp category_for_path("posts/" <> _rest), do: :posts
   defp category_for_path("scripts/" <> _rest), do: :scripts
   defp category_for_path("templates/" <> _rest), do: :templates
diff --git a/priv/ui/app.css b/priv/ui/app.css
index 29eb90b..9c90673 100644
--- a/priv/ui/app.css
+++ b/priv/ui/app.css
@@ -393,6 +393,23 @@ button {
   background-color: var(--vscode-activityBar-foreground);
 }
 
+.activity-bar-badge {
+  position: absolute;
+  top: 8px;
+  right: 8px;
+  min-width: 16px;
+  height: 16px;
+  padding: 0 4px;
+  font-size: 10px;
+  font-weight: 600;
+  background-color: var(--vscode-activityBarBadge-background);
+  color: var(--vscode-activityBarBadge-foreground);
+  border-radius: 8px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+}
+
 .activity-bar-item svg,
 .tab-icon svg {
   display: block;
diff --git a/test/bds/desktop/shell_live_test.exs b/test/bds/desktop/shell_live_test.exs
index c6b2e56..8b3cda6 100644
--- a/test/bds/desktop/shell_live_test.exs
+++ b/test/bds/desktop/shell_live_test.exs
@@ -26,6 +26,7 @@ defmodule BDS.Desktop.ShellLiveTest do
     {:ok, _project} = Projects.set_active_project(project.id)
 
     original_shell_platform = Application.get_env(:bds, :shell_platform)
+    original_git_remote_state_provider = Application.get_env(:bds, :git_remote_state_provider)
 
     on_exit(fn ->
       if is_nil(original_shell_platform) do
@@ -33,6 +34,12 @@ defmodule BDS.Desktop.ShellLiveTest do
       else
         Application.put_env(:bds, :shell_platform, original_shell_platform)
       end
+
+      if is_nil(original_git_remote_state_provider) do
+        Application.delete_env(:bds, :git_remote_state_provider)
+      else
+        Application.put_env(:bds, :git_remote_state_provider, original_git_remote_state_provider)
+      end
     end)
 
     %{project: project, temp_dir: temp_dir}
@@ -158,6 +165,18 @@ defmodule BDS.Desktop.ShellLiveTest do
     refute html =~ ~s(data-testid="window-titlebar-menu-dropdown")
   end
 
+  test "shell live renders the legacy git activity badge from remote behind count" do
+    Application.put_env(:bds, :git_remote_state_provider, fn _project_id, _opts ->
+      {:ok, %{local_branch: "main", upstream_branch: "origin/main", has_upstream: true, ahead: 0, behind: 7}}
+    end)
+
+    {:ok, _view, html} = live_isolated(build_conn(), BDS.Desktop.ShellLive)
+
+    assert html =~ ~s(data-view="git")
+    assert html =~ ~s(class="activity-bar-badge")
+    assert html =~ ">7<"
+  end
+
   test "sidebar open supports preview and pin intents for entity tabs" do
     {:ok, view, _html} = live_isolated(build_conn(), BDS.Desktop.ShellLive)
 
diff --git a/test/bds/git_test.exs b/test/bds/git_test.exs
index 74743c5..e2e1cb7 100644
--- a/test/bds/git_test.exs
+++ b/test/bds/git_test.exs
@@ -72,6 +72,22 @@ defmodule BDS.GitTest do
     assert repo.current_branch == "main"
   end
 
+  test "remote_state reports upstream ahead and behind counts", %{project: project} do
+    runner = fake_runner(fn
+      "git", ["rev-parse", "--abbrev-ref", "HEAD"], _opts -> {"main\n", 0}
+      "git", ["rev-parse", "--abbrev-ref", "--symbolic-full-name", "@{upstream}"], _opts -> {"origin/main\n", 0}
+      "git", ["rev-list", "--count", "origin/main..HEAD"], _opts -> {"2\n", 0}
+      "git", ["rev-list", "--count", "HEAD..origin/main"], _opts -> {"5\n", 0}
+    end)
+
+    assert {:ok, remote_state} = Git.remote_state(project.id, runner: runner)
+    assert remote_state.local_branch == "main"
+    assert remote_state.upstream_branch == "origin/main"
+    assert remote_state.has_upstream == true
+    assert remote_state.ahead == 2
+    assert remote_state.behind == 5
+  end
+
   test "fetch, pull, push, commit_all, reconcile, and prune_lfs_cache run non-interactively", %{
     project: project
   } do
diff --git a/test/bds/ui/shell_test.exs b/test/bds/ui/shell_test.exs
index c25dcf7..adbf191 100644
--- a/test/bds/ui/shell_test.exs
+++ b/test/bds/ui/shell_test.exs
@@ -136,11 +136,17 @@ defmodule BDS.UI.ShellTest do
     template = File.read!("/Users/gb/Projects/bDS2/lib/bds/desktop/shell_live/index.html.heex")
 
     assert css =~ "color: var(--vscode-activityBar-foreground)"
+    assert css =~ ".activity-bar-badge"
     assert css =~ ".tab-actions"
     assert css =~ ".tab-dirty-indicator"
     assert css =~ ".tab.dirty .tab-close"
     assert css =~ ".tab:focus-visible"
     assert css =~ ".window-titlebar-action-button:focus"
+    assert css =~ ".panel-tab.active"
+    assert css =~ "border-bottom-color: var(--vscode-focusBorder);"
+    assert css =~ ".sidebar-section-header"
+    assert css =~ "justify-content: space-between"
+    assert css =~ "align-items: center"
     assert css =~ "padding-right: calc(10px + var(--bds-titlebar-overlay-right, 0px));"
     assert live_js =~ "windowControlsOverlay"
     assert live_js =~ "geometrychange"
@@ -150,6 +156,7 @@ defmodule BDS.UI.ShellTest do
     assert live_js =~ "event.preventDefault()"
     assert live_js =~ "this.pushEvent(\"shortcut\""
     assert template =~ "data-shortcuts={encoded_shortcuts(@client_shortcuts)}"
+    assert template =~ "activity-bar-badge"
     assert template =~ "tab-actions"
     assert template =~ "tab-dirty-indicator"
   end