diff --git a/lib/aprsme/spatial_pubsub.ex b/lib/aprsme/spatial_pubsub.ex
index 97ead72..98f7b88 100644
--- a/lib/aprsme/spatial_pubsub.ex
+++ b/lib/aprsme/spatial_pubsub.ex
@@ -18,42 +18,64 @@ defmodule Aprsme.SpatialPubSub do
   Register a client with their current viewport bounds.
   """
   def register_viewport(client_id, bounds) do
-    GenServer.call(__MODULE__, {:register_viewport, client_id, bounds})
+    with_server({:error, :not_running}, fn ->
+      GenServer.call(__MODULE__, {:register_viewport, client_id, bounds})
+    end)
   end
 
   @doc """
   Update a client's viewport bounds.
   """
   def update_viewport(client_id, bounds) do
-    GenServer.call(__MODULE__, {:update_viewport, client_id, bounds})
+    with_server({:error, :not_running}, fn ->
+      GenServer.call(__MODULE__, {:update_viewport, client_id, bounds})
+    end)
   end
 
   @doc """
   Unregister a client.
   """
   def unregister_client(client_id) do
-    GenServer.cast(__MODULE__, {:unregister_client, client_id})
+    with_server(:ok, fn ->
+      GenServer.cast(__MODULE__, {:unregister_client, client_id})
+    end)
   end
 
   @doc """
   Broadcast a packet to all clients whose viewports contain the packet's location.
   """
   def broadcast_packet(packet) do
-    GenServer.cast(__MODULE__, {:broadcast_packet, packet})
+    with_server(:ok, fn ->
+      GenServer.cast(__MODULE__, {:broadcast_packet, packet})
+    end)
   end
 
   @doc """
   Get statistics about spatial filtering.
   """
   def get_stats do
-    GenServer.call(__MODULE__, :get_stats)
+    with_server(
+      %{
+        total_broadcasts: 0,
+        filtered_broadcasts: 0,
+        total_packets: 0,
+        clients_count: 0,
+        grid_cells: 0,
+        avg_clients_per_cell: 0.0
+      },
+      fn ->
+        GenServer.call(__MODULE__, :get_stats)
+      end
+    )
   end
 
   @doc """
   Start telemetry reporting for LiveDashboard integration.
   """
   def start_telemetry_reporting do
-    GenServer.cast(__MODULE__, :start_telemetry_reporting)
+    with_server(:ok, fn ->
+      GenServer.cast(__MODULE__, :start_telemetry_reporting)
+    end)
   end
 
   # Server callbacks
@@ -439,4 +461,12 @@ defmodule Aprsme.SpatialPubSub do
       %{}
     )
   end
+
+  defp with_server(default, fun) do
+    if Process.whereis(__MODULE__) do
+      fun.()
+    else
+      default
+    end
+  end
 end
diff --git a/lib/aprsme/streaming_packets_pubsub.ex b/lib/aprsme/streaming_packets_pubsub.ex
index 6a2a19e..42848ce 100644
--- a/lib/aprsme/streaming_packets_pubsub.ex
+++ b/lib/aprsme/streaming_packets_pubsub.ex
@@ -32,28 +32,36 @@ defmodule Aprsme.StreamingPacketsPubSub do
     - :ok
   """
   def subscribe_to_bounds(pid, bounds) do
-    GenServer.call(__MODULE__, {:subscribe, pid, bounds})
+    with_server({:error, :not_running}, fn ->
+      GenServer.call(__MODULE__, {:subscribe, pid, bounds})
+    end)
   end
 
   @doc """
   Unsubscribe from packet notifications.
   """
   def unsubscribe(pid) do
-    GenServer.call(__MODULE__, {:unsubscribe, pid})
+    with_server(:ok, fn ->
+      GenServer.call(__MODULE__, {:unsubscribe, pid})
+    end)
   end
 
   @doc """
   Broadcast a packet to all subscribers whose bounds contain the packet's location.
   """
   def broadcast_packet(packet) do
-    GenServer.cast(__MODULE__, {:broadcast, packet})
+    with_server(:ok, fn ->
+      GenServer.cast(__MODULE__, {:broadcast, packet})
+    end)
   end
 
   @doc """
   List all active subscribers and their bounds.
   """
   def list_subscribers do
-    GenServer.call(__MODULE__, :list_subscribers)
+    with_server([], fn ->
+      GenServer.call(__MODULE__, :list_subscribers)
+    end)
   end
 
   # Server Callbacks
@@ -200,4 +208,12 @@ defmodule Aprsme.StreamingPacketsPubSub do
   defp test_env? do
     Application.get_env(:aprsme, :env) == :test
   end
+
+  defp with_server(default, fun) do
+    if Process.whereis(__MODULE__) do
+      fun.()
+    else
+      default
+    end
+  end
 end
diff --git a/test/aprsme/spatial_pubsub_test.exs b/test/aprsme/spatial_pubsub_test.exs
index b7a4636..c4810bb 100644
--- a/test/aprsme/spatial_pubsub_test.exs
+++ b/test/aprsme/spatial_pubsub_test.exs
@@ -97,4 +97,41 @@ defmodule Aprsme.SpatialPubSubTest do
       SpatialPubSub.unregister_client(client_id)
     end
   end
+
+  describe "when the server is not running" do
+    setup do
+      pid = Process.whereis(SpatialPubSub)
+
+      if pid do
+        GenServer.stop(pid)
+      end
+
+      on_exit(fn ->
+        if !Process.whereis(SpatialPubSub) do
+          start_supervised!({SpatialPubSub, []})
+        end
+      end)
+
+      :ok
+    end
+
+    test "public APIs return safe defaults instead of crashing" do
+      bounds = %{north: 41.0, south: 40.0, east: -73.0, west: -74.0}
+
+      assert {:error, :not_running} = SpatialPubSub.register_viewport("missing", bounds)
+      assert {:error, :not_running} = SpatialPubSub.update_viewport("missing", bounds)
+      assert :ok = SpatialPubSub.unregister_client("missing")
+      assert :ok = SpatialPubSub.broadcast_packet(%{lat: 40.5, lon: -73.5})
+      assert :ok = SpatialPubSub.start_telemetry_reporting()
+
+      assert SpatialPubSub.get_stats() == %{
+               total_broadcasts: 0,
+               filtered_broadcasts: 0,
+               total_packets: 0,
+               clients_count: 0,
+               grid_cells: 0,
+               avg_clients_per_cell: 0.0
+             }
+    end
+  end
 end
diff --git a/test/aprsme/streaming_packets_pubsub_test.exs b/test/aprsme/streaming_packets_pubsub_test.exs
index 6905cc0..d1a1784 100644
--- a/test/aprsme/streaming_packets_pubsub_test.exs
+++ b/test/aprsme/streaming_packets_pubsub_test.exs
@@ -140,6 +140,33 @@ defmodule Aprsme.StreamingPacketsPubSubTest do
     end
   end
 
+  describe "when the server is not running" do
+    setup do
+      pid = Process.whereis(StreamingPacketsPubSub)
+
+      if pid do
+        GenServer.stop(pid)
+      end
+
+      on_exit(fn ->
+        if !Process.whereis(StreamingPacketsPubSub) do
+          start_supervised!({StreamingPacketsPubSub, []})
+        end
+      end)
+
+      :ok
+    end
+
+    test "returns safe defaults instead of crashing" do
+      bounds = %{north: 40.0, south: 30.0, east: -70.0, west: -80.0}
+
+      assert {:error, :not_running} = StreamingPacketsPubSub.subscribe_to_bounds(self(), bounds)
+      assert :ok = StreamingPacketsPubSub.unsubscribe(self())
+      assert :ok = StreamingPacketsPubSub.broadcast_packet(%{latitude: 35.0, longitude: -75.0})
+      assert [] == StreamingPacketsPubSub.list_subscribers()
+    end
+  end
+
   describe "performance" do
     test "handles high volume of packets efficiently" do
       bounds = %{north: 90.0, south: -90.0, east: 180.0, west: -180.0}