diff --git a/tests/test_net_lands.gd b/tests/test_net_lands.gd
index 676e8c5..e636559 100644
--- a/tests/test_net_lands.gd
+++ b/tests/test_net_lands.gd
@@ -53,8 +53,11 @@ func _run() -> void:
 	Net.arrived.connect(func(l): _arrived = l)
 	for d in [SRV, BOBS]:
 		_rm_tree(d)
-	_spawn(["--server", "--port", str(PORT), "--config", SRV + "/server.json",
-		"--server-name", "Lands Test", "--seed", str(SEED), "--debug-cheats", "--no-creatures"])
+	# (EMBERWILD_SERVER_BIN=<an exported game>: the hub, and the land servers
+	# it starts, are that build: checks a release does it too.)
+	_spawn(["--server", "--port", str(PORT), "--config", ProjectSettings.globalize_path(SRV + "/server.json"),
+		"--server-name", "Lands Test", "--seed", str(SEED), "--debug-cheats", "--no-creatures"], "",
+		OS.get_environment("EMBERWILD_SERVER_BIN"))
 	await _sleep(4.0)
 	await _body()
 	if world != null and is_instance_valid(world):
@@ -370,15 +373,17 @@ func _bob_result(n: int, limit: float) -> Dictionary:
 	var d: Variant = JSON.parse_string(FileAccess.get_file_as_string(path)) if FileAccess.file_exists(path) else null
 	return d if d is Dictionary else {"error": "Bob gave no answer to command %d" % n}
 
-func _spawn(user_args: Array, script: String = "") -> int:
-	var args := PackedStringArray(["--headless", "--path", ProjectSettings.globalize_path("res://")])
+func _spawn(user_args: Array, script: String = "", bin: String = "") -> int:
+	var args := PackedStringArray(["--headless"])
+	if bin.is_empty():
+		args.append_array(["--path", ProjectSettings.globalize_path("res://")])
 	if not script.is_empty():
 		args.append_array(["--script", script])
 	args.append("--")
 	for x in user_args:
 		args.append(str(x))
 	args.append_array(["--exit-with", str(OS.get_process_id())])
-	var pid := OS.create_process(OS.get_executable_path(), args)
+	var pid := OS.create_process(OS.get_executable_path() if bin.is_empty() else bin, args)
 	_pids.append(pid)
 	return pid
 
diff --git a/tools/site/index.html b/tools/site/index.html
index 9d5bb9c..2b23f65 100644
--- a/tools/site/index.html
+++ b/tools/site/index.html
@@ -101,9 +101,13 @@
   <section aria-labelledby="host-title">
     <h2 id="host-title">Playing with friends</h2>
     <p>Choose <b>Host Game</b> on the title screen, and friends choose <b>Join Game</b>
-      with your address (UDP port 24242). Everyone needs the same version. A spare
-      computer can run a dedicated server from the same download:
-      <code>Emberwild --headless -- --server</code>.</p>
+      with your address (UDP port 24242). Everyone needs the same version. On the same
+      network, or over Tailscale, that's all. For friends over the internet, forward
+      <b>UDP 24242 and 24243</b> on your router: the Cove runs as its own server on the
+      next port, started when someone first goes there. A spare computer can run a
+      dedicated server from the same download:
+      <code>Emberwild --headless -- --server</code>.
+      <a href="guide.html#multiplayer">More in the guide</a>.</p>
   </section>
 </main>