diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 7aa9927..71ba16c 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -480,6 +480,9 @@ importers:
       firebase-admin:
         specifier: ^11.10.1
         version: 11.10.1
+      protocol:
+        specifier: workspace:*
+        version: link:../protocol
       tracker-list:
         specifier: workspace:*
         version: link:../tracker-list
diff --git a/server/src/autoupdater.ts b/server/src/autoupdater.ts
index a6c72cb..400da0a 100644
--- a/server/src/autoupdater.ts
+++ b/server/src/autoupdater.ts
@@ -17,10 +17,8 @@ https.get(
 
         file.on("finish", () => {
             fs.chmodSync(`${dir}/${appname}`, "755");
-            setTimeout(() => {
-                // this timeout shouldn't be needed, but it is
-                start();
-            }, 2000);
+            // this timeout shouldn't be needed, but it is
+            setTimeout(start, 2000);
         });
     })
 
diff --git a/server/src/dev.ts b/server/src/dev.ts
index 6f589c3..20fadb4 100644
--- a/server/src/dev.ts
+++ b/server/src/dev.ts
@@ -6,6 +6,7 @@ import { AdriftServer, connectTracker } from "./server";
 
 import WebSocket from "isomorphic-ws";
 import { answerRtc, bufferToArrayBuffer } from "./rtc";
+import { PROTOCOL_VERSION } from "protocol";
 
 dotenv.config();
 
@@ -50,9 +51,9 @@ app.ws("/dev-ws", (ws, _req) => {
 });
 
 try {
-  let tracker = new WebSocket("ws://localhost:17776/join");
+  let tracker = new WebSocket(`ws://localhost:17776/join?protocol=${PROTOCOL_VERSION}`);
   tracker.onerror = console.error;
   connectTracker(tracker);
-} catch (_) {}
+} catch (_) { }
 
 app.listen(3000, () => console.log("listening"));
diff --git a/tracker/package.json b/tracker/package.json
index 763310e..1656d8c 100644
--- a/tracker/package.json
+++ b/tracker/package.json
@@ -17,6 +17,7 @@
     "firebase": "^10.1.0",
     "firebase-admin": "^11.10.1",
     "tracker-list": "workspace:*",
+    "protocol": "workspace:*",
     "ts-node": "^10.9.1",
     "typescript": "^5.1.6",
     "uuid": "^9.0.0"
diff --git a/tracker/src/main.ts b/tracker/src/main.ts
index 76e5060..42fec86 100644
--- a/tracker/src/main.ts
+++ b/tracker/src/main.ts
@@ -10,6 +10,8 @@ import { WebSocket } from "ws";
 
 import { v4 as uuid } from "uuid";
 
+import { PROTOCOL_VERSION } from "protocol";
+
 dotenv.config();
 
 let members: Record<string, WebSocket> = {};
@@ -70,16 +72,21 @@ reff.on("value", snapshot => {
 });
 
 
-app.ws("/join", (ws, _req) => {
+app.ws("/join", (ws, req) => {
+  let ver = new URL(`https://a/${req.url}`).searchParams.get("protocol");
+
+  if (ver != PROTOCOL_VERSION) {
+    ws.close();
+  }
 
   let id = uuid();
-  console.log(_req.ip);
+  console.log(req.ip);
   console.log(`ws connect of id ${id}`);
 
   members[id] = ws;
 
   ws.onclose = () => {
-    console.log(`${_req.ip} disconnected`);
+    console.log(`${req.ip} disconnected`);
     delete members[id];
   };
   setInterval(() => {