SSinstancing (I need to test this with 2 machines)

code/controllers/subsystem/instancing.dm

@@ -0,0 +1,63 @@
+SUBSYSTEM_DEF(instancing)
+	name = "Instancing"
+	runlevels = RUNLEVEL_INIT | RUNLEVEL_LOBBY | RUNLEVEL_SETUP | RUNLEVEL_GAME | RUNLEVEL_POSTGAME
+	/// Have we announced startup yet
+	var/startup_announced = FALSE
+	/// Is a check currently running?
+	var/check_running = FALSE
+
+/datum/controller/subsystem/instancing/Initialize(start_timeofday)
+	// Do an initial peer check
+	check_peers()
+	return ..()
+
+/datum/controller/subsystem/instancing/fire(resumed)
+	check_peers()
+
+
+/**
+  * Refreshes all peers on the server
+  *
+  * Called periodically during fire() as well as when a new peer reports itself as online
+  * Only one instance of this proc may run at a time
+  *
+  */
+/datum/controller/subsystem/instancing/proc/check_peers()
+	set waitfor = FALSE // This has sleeps if it cant topic so we dont want to bog things down
+	if(check_running)
+		return
+
+	check_running = TRUE // Dont allow multiple of these
+	// A NOTE TO ANYONE ELSE WHO LOOKS AT THIS
+	// THESE TIMINGS ARE A FUCKING NIGHTMARE AND YOU WILL NEED DEBUG LOGGING TO TEST THEM
+	// DO NOT FUCK WITH THE TIMINGS -aa
+	for(var/datum/peer_server/PS in GLOB.configuration.instancing.peers)
+		// If the server hasnt been discovered and its been more than 5 minutes
+		if((!PS.discovered && PS.last_operation_time + 5 MINUTES > world.time))
+			continue
+
+		if(PS.last_operation_time + 1 MINUTES > world.time)
+			continue // Only run main operations once every minute anyway
+
+		var/peer_response = world.Export("byond://[PS.internal_ip]:[PS.server_port]?server_discovery&key=[PS.commskey]")
+		if(!peer_response)
+			PS.online = FALSE // Peer is offline
+			PS.last_operation_time = world.time
+			continue
+
+		// We got a response
+		PS.discovered = TRUE
+		PS.online = TRUE
+		var/list/peer_data = json_decode(peer_response)
+
+		PS.external_ip = peer_data["external_ip"]
+		PS.server_id = peer_data["server_id"]
+		PS.server_name = peer_data["server_name"]
+		PS.playercount = peer_data["playercount"]
+
+		PS.last_operation_time = world.time
+
+	check_running = FALSE
+
+/datum/controller/subsystem/instancing/proc/message_all_peers(include_offline = FALSE)
+	return