diff --git a/package.json b/package.json
index 7f46b04..807d4a0 100644
--- a/package.json
+++ b/package.json
@@ -29,7 +29,7 @@
     "eslint-config-prettier": "6.10.1",
     "eslint-plugin-prettier": "3.1.4",
     "express": "4.17.1",
-    "prettier": "1.19.1",
+    "prettier": "2.0.5",
     "socket.io": "2.3.0"
   },
   "devDependencies": {
diff --git a/src/index.ts b/src/index.ts
index 351b6ad..ac9f2a7 100755
--- a/src/index.ts
+++ b/src/index.ts
@@ -17,21 +17,21 @@ server.listen(port, () => {
 });
 
 const io = socketIO(server, {
-  handlePreflightRequest: function(req, res) {
+  handlePreflightRequest: function (req, res) {
     var headers = {
       "Access-Control-Allow-Headers": "Content-Type, Authorization",
       "Access-Control-Allow-Origin": req.header ? req.header.origin : "*",
-      "Access-Control-Allow-Credentials": true
+      "Access-Control-Allow-Credentials": true,
     };
     res.writeHead(200, headers);
     res.end();
-  }
+  },
 });
 
-io.on("connection", socket => {
+io.on("connection", (socket) => {
   ioDebug("connection established!");
   io.to(`${socket.id}`).emit("init-room");
-  socket.on("join-room", roomID => {
+  socket.on("join-room", (roomID) => {
     socketDebug(`${socket.id} has joined ${roomID}`);
     socket.join(roomID);
     if (io.sockets.adapter.rooms[roomID].length <= 1) {
@@ -67,7 +67,7 @@ io.on("connection", socket => {
     const rooms = io.sockets.adapter.rooms;
     for (const roomID in socket.rooms) {
       const clients = Object.keys(rooms[roomID].sockets).filter(
-        id => id !== socket.id
+        (id) => id !== socket.id
       );
       if (clients.length > 0) {
         socket.broadcast.to(roomID).emit("room-user-change", clients);
diff --git a/yarn.lock b/yarn.lock
index 6931019..2c5e226 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1054,10 +1054,10 @@ prettier-linter-helpers@^1.0.0:
   dependencies:
     fast-diff "^1.1.2"
 
-prettier@1.19.1:
-  version "1.19.1"
-  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.19.1.tgz#f7d7f5ff8a9cd872a7be4ca142095956a60797cb"
-  integrity sha512-s7PoyDv/II1ObgQunCbB9PdLmUcBZcnWOcxDh7O0N/UwDEsHyqkW+Qh28jW+mVuCdx7gLB0BotYI1Y6uI9iyew==
+prettier@2.0.5:
+  version "2.0.5"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-2.0.5.tgz#d6d56282455243f2f92cc1716692c08aa31522d4"
+  integrity sha512-7PtVymN48hGcO4fGjybyBSIWDsLU4H4XlvOHfq91pz9kkGlonzwTfYkaIEwiRg/dAJF9YlbsduBAgtYLi+8cFg==
 
 progress@^2.0.0:
   version "2.0.3"