diff --git a/server.js b/server.js
index b17abcb..ea10c3e 100644
--- a/server.js
+++ b/server.js
@@ -1,5 +1,5 @@
-import "fs"
-import {format} from "util"
+const fs = require("fs")
+const format = require("util").format
 
 
 /**
diff --git a/server_esm.js b/server_esm.js
index e2c7669..5bab1ed 100644
--- a/server_esm.js
+++ b/server_esm.js
@@ -84,7 +84,7 @@ function log_info(level, ...info) {
 }
 console.log = log_info;
 
-const WebSocket = { Server: ws }.Server;
+const WebSocket = ws.Server;
 
 import {EventEmitter} from 'events';
 import merge from 'merge-descriptors';