diff --git a/Express/barAndCafe/src/app.ts b/Express/barAndCafe/src/app.ts
new file mode 100644
index 0000000..943d8a9
--- /dev/null
+++ b/Express/barAndCafe/src/app.ts
@@ -0,0 +1,21 @@
+import express from "express";
+
+/**
+ * Initialize Express application instance.
+ * @returns An initialized Express application object.
+ */
+const app = express();
+
+/**
+ * Handle GET request for homepage route ('/').
+ * Send back a simple text response.
+ * @param {express.Request} req - HTTP Request object.
+ * @param {express.Response} res - HTTP Response object.
+ */
+function getRoot(req: express.Request, res: express.Response) {
+    res.send("hello world from dev");
+}
+
+app.get("/", getRoot);
+
+export default app;
\ No newline at end of file
diff --git a/Express/barAndCafe/index.ts b/Express/barAndCafe/src/server.ts
similarity index 61%
rename from Express/barAndCafe/index.ts
rename to Express/barAndCafe/src/server.ts
index 7d6d177..625a94c 100644
--- a/Express/barAndCafe/index.ts
+++ b/Express/barAndCafe/src/server.ts
@@ -1,16 +1,10 @@
-import express from "express";
 import * as dotenv from "dotenv";
+import app from "./app";
 
 dotenv.config({path: '../../.env'})
 
 const port = parseInt(process.env.BAR_PORT || '3000')
 
-const app = express();
-
-app.get("/", (req, res) => {
-    res.send("helloworld form dev")
-})
-
 app.listen(port, () =>{
     console.log(`serveur running in ${port}`)
 })
\ No newline at end of file