diff --git a/demo/index.html b/demo/index.html
index 48095af..612b4f0 100644
--- a/demo/index.html
+++ b/demo/index.html
@@ -81,6 +81,7 @@
   <script src="https://cdn.jsdelivr.net/npm/@cap.js/widget"></script>
   <script src="https://cdn.jsdelivr.net/npm/@cap.js/widget/cap-floating.min.js"></script>
   
-  <!-- <script src="/cap.js"></script> -->
-  <!-- <script src="/cap-floating.js"></script> -->
+  <!-- to use local resources, uncomment this: -->
+  <!-- <script src="/cap.js"></script>
+       <script src="/cap-floating.js"></script> -->
 </html>
diff --git a/demo/package.json b/demo/package.json
index 5077438..2abf940 100644
--- a/demo/package.json
+++ b/demo/package.json
@@ -6,11 +6,13 @@
   "type": "commonjs",
   "main": "server.js",
   "scripts": {
-    "start": "bun server.js",
+    "start": "bun run server.js",
+    "dev": "bun run --watch server.js",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "dependencies": {
     "@cap.js/server": "^1.0.5",
-    "express": "^4.21.2"
+    "@fastify/static": "^8.1.1",
+    "fastify": "^5.2.1"
   }
 }
diff --git a/demo/server.js b/demo/server.js
index 07fa0fe..4c99670 100644
--- a/demo/server.js
+++ b/demo/server.js
@@ -1,23 +1,32 @@
-const express = require("express");
-const Cap = require("@cap.js/server");
-
-const app = express();
-
-app.use(express.json());
-
-// app.use("/cap.js", express.static('../widget/src/cap.js'));
-// app.use("/cap-floating.js", express.static('../widget/src/cap-floating.js'));
+import path from "path";
+import Cap from "@cap.js/server";
+import fastifyStatic from "@fastify/static";
+import Fastify from "fastify";
 
+const fastify = Fastify();
 const cap = new Cap({
   tokens_store_path: ".data/tokensList.json",
 });
 
-app.get("/", (req, res) => {
-  res.sendFile("index.html", { root: __dirname });
+fastify.register(fastifyStatic, {
+  root: path.join(__dirname),
+  prefix: "/",
 });
 
-app.post("/api/challenge", (req, res) => {
-  res.json(
+fastify.get("/", (req, res) => {
+  res.sendFile("index.html");
+});
+
+fastify.get("/cap.js", (req, res) => {
+  res.sendFile("../widget/src/cap.js");
+});
+
+fastify.get("/cap-floating.js", (req, res) => {
+  res.sendFile("../widget/src/cap-floating.js");
+});
+
+fastify.post("/api/challenge", (req, res) => {
+  res.send(
     cap.createChallenge({
       challengeCount: 32,
       challengeDifficulty: 3,
@@ -25,15 +34,15 @@ app.post("/api/challenge", (req, res) => {
   );
 });
 
-app.post("/api/redeem", async (req, res) => {
+fastify.post("/api/redeem", async (req, res) => {
   const { token, solutions } = req.body;
   if (!token || !solutions) {
-    return res.status(400).json({ success: false });
+    return res.code(400).send({ success: false });
   }
-  
-  res.json(await cap.redeemChallenge({ token, solutions }));
+
+  res.send(await cap.redeemChallenge({ token, solutions }));
 });
 
-app.listen(3000, () => {
-  console.log("Listening on http://localhost:3000");
+fastify.listen({ port: 3000, host: "0.0.0.0" }).then(() => {
+  console.log("Server is running on http://localhost:3000");
 });
diff --git a/server/index.test.js b/server/index.test.js
index 25f3ee7..ba28a7d 100644
--- a/server/index.test.js
+++ b/server/index.test.js
@@ -1,6 +1,5 @@
 const express = require('express');
 const crypto = require('crypto');
-const fs = require('fs').promises;
 const Cap = require('./index.js');
 
 const app = express();