diff --git a/02-nodejs/authenticationServer.js b/02-nodejs/authenticationServer.js
index c5278b94..b080427f 100644
--- a/02-nodejs/authenticationServer.js
+++ b/02-nodejs/authenticationServer.js
@@ -29,9 +29,150 @@
   Testing the server - run `npm run test-authenticationServer` command in terminal
  */
 
-const express = require("express")
+const express = require("express");
+const bodyParser = require("body-parser");
 const PORT = 3000;
 const app = express();
+let users = [];
+
+app.use(bodyParser.json());
+
+app.post("/signup", (req, res) => {
+  const user = req.body;
+  let userAlreadyExists = false;
+  for (let i = 0; i < users.length; i++) {
+    if (users[i].email === user.email) {
+      userAlreadyExists = true;
+      break;
+    }
+  }
+    if (userAlreadyExists) {
+      res.sendStatus(400);
+    } else {
+      users.push(user);
+      res.status(201).send("Signup successful");
+    }
+});
+
+app.post("/login", (req, res) => {
+  const user = req.body;
+  let userfound = null;
+  for (let i = 0; i < users.length; i++) {
+    if (users[i].email === user.email && users[i].password === user.password) {
+      userfound = users[i];
+      break;
+    }
+  }
+  if (userfound) {
+    res.json({
+      firstname: userfound.firstname,
+      lastname: userfound.lastname,
+      id: userfound.id
+    });
+  }
+  else {
+    res.sendStatus(401);
+  }
+});
+
+app.get("/data", (req, res) => {
+  let email = req.headers.email;
+  let password = req.headers.password;
+  let userfound = false;
+  for(let i = 0 ; i < users.length; i++){
+    if(users[i].email === email && users[i].password === password){
+      userfound = users[i];
+      break;
+    }
+  }
+  if(userfound){
+    res.json(userfound);
+  }
+  else{
+    res.sendStatus(401);
+  }
+  });
 // write your logic here, DONT WRITE app.listen(3000) when you're running tests, the tests will automatically start the server
 
-module.exports = app;
+app.use((req, res) => {
+  res.sendStatus(404);
+});
+
+app.listen(PORT,() =>{
+  console.log(`Server is running on port ${PORT}`);
+});
+
+
+// const express = require("express");
+// const bodyParser = require("body-parser");
+// const PORT = 3000;
+// const app = express();
+// let users = [];
+
+// app.use(bodyParser.json());
+
+// app.post("/signup", (req, res) => {
+//   const user = req.body;
+//   let userAlreadyExists = false; // Fixed typo here
+//   for (let i = 0; i < users.length; i++) {
+//     if (users[i].email === user.email) {
+//       userAlreadyExists = true;
+//       break;
+//     }
+//   }
+//   if (userAlreadyExists) {
+//     res.sendStatus(400);
+//   } else {
+//     users.push(user);
+//     res.status(201).send("Signup successful");
+//   }
+// });
+
+// app.post("/login", (req, res) => {
+//   const user = req.body;
+//   let userFound = null; // Improved variable naming consistency
+//   for (let i = 0; i < users.length; i++) {
+//     if (users[i].email === user.email && users[i].password === user.password) {
+//       userFound = users[i];
+//       break;
+//     }
+//   }
+//   if (userFound) {
+//     res.json({
+//       firstname: userFound.firstname,
+//       lastname: userFound.lastname,
+//       id: userFound.id
+//     });
+//   } else {
+//     res.sendStatus(401);
+//   }
+// });
+
+// app.get("/data", (req, res) => {
+//   let email = req.headers.email;
+//   let password = req.headers.password;
+//   let userFound = false;
+//   for (let i = 0; i < users.length; i++) {
+//     if (users[i].email === email && users[i].password === password) {
+//       userFound = users[i];
+//       break;
+//     }
+//   }
+//   if (userFound) {
+//     res.json(userFound);
+//   } else {
+//     res.sendStatus(401);
+//   }
+// });
+
+// // Correctly placing the 404 handler
+// app.use((req, res) => {
+//   res.sendStatus(404);
+// });
+
+// // Corrected the app.listen call
+// app.listen(PORT, () => {
+//   console.log(`Server is running on port ${PORT}`);
+// });
+
+// module.exports = app;
diff --git a/02-nodejs/fileServer.js b/02-nodejs/fileServer.js
index 82e7719b..9a2bf0d9 100644
--- a/02-nodejs/fileServer.js
+++ b/02-nodejs/fileServer.js
@@ -19,7 +19,40 @@
 const express = require('express');
 const fs = require('fs');
 const path = require('path');
+const port = 3000;
 const app = express();
 
+app.get('/files', (req,res) => {
+  const directoryPath = path.join( __dirname, 'files');
+  fs.readdir(directoryPath,(err, files) => {
+    // err? res.status(500).send() : res.status(200).json(files);
+    if(err){
+      res.status(500).send();
+    } else{
+      res.status(200).json(files);
+    }
+  })
+})
+
+
+app.get('/files/:filename',(req,res) =>{
+  const filename = req.params.filename;
+  fs.readFile(path.join( __dirname,'./files',filename), 'utf8', (err, data) => {
+    if(err){
+      res.status(404).send('File not found');
+    } else{
+      res.status(200).send(data);
+    }
+  })
+})
+
+// app.listen(port, () => {
+//   console.log(`Server is running on port ${port}`);
+// });
+
+app.use((req, res) =>{
+  res.status(404).send();
+})
 
 module.exports = app;
+
diff --git a/02-nodejs/solutions/todos.json b/02-nodejs/solutions/todos.json
deleted file mode 100644
index e69de29b..00000000
diff --git a/02-nodejs/todoServer.js b/02-nodejs/todoServer.js
index cffc7d60..d254a0bf 100644
--- a/02-nodejs/todoServer.js
+++ b/02-nodejs/todoServer.js
@@ -39,11 +39,122 @@
 
   Testing the server - run `npm run test-todoServer` command in terminal
  */
+const bodyParser = require('body-parser'); 
 const express = require('express');
-const bodyParser = require('body-parser');
+const fs = require('fs');
+const path = require('path');
+const port = 3000;
 
 const app = express();
+// Adjust the path to include the 'solutions' directory
+const filePath = path.join(__dirname, 'todos.json');
 
 app.use(bodyParser.json());
+let todos = [];
+
+function findIndex(arr, id){
+  for(let i = 0; i < arr.length; i++){
+    if(arr[i].id === id) return i;
+  }
+  return "Error: Something went wrong!";
+}
+
+function removeIndex(arr, id){
+  let newArray = [];
+  for(let i = 0; i <arr.length; i++){
+    if(arr[i].id !== id) return newArray.push(arr[i]);
+  }
+  return "Error: Something went wrong!";
+}
+
+app.get('/todos', (req, res) => {
+  console.log(filePath);
+  fs.readFile(filePath, 'utf8', (err, data) => {
+    if(err) throw err;
+    res.json(JSON.parse(data));
+  })
+});
+
+app.get('/todos/:id', (req, res) => {
+  fs.readFile(filePath, 'utf8', (err, data) => {
+    if(err) throw err;
+    const todos = JSON.parse(data);
+    const todoIndex = findIndex(todos, parseInt(todos, parseInt(req.params.id)));
+    if(todoIndex === -1){
+      res.status(404).send();
+    }
+    else{
+      res.json(todos[todoIndex]);
+    }
+  })
+})
+
+app.post('/todos', (req, res) => {
+  const newTodo = {
+    id: Math.floor(Math.random() * 1000000),
+    title: req.body.title,
+    description: req.body.description
+  }
+  fs.readFile(filePath, 'utf8', (err, data) => {
+    if(err) throw err;
+    const todos = JSON.parse(data);
+    todos.push(newTodo);
+    fs.writeFille(filePath, JSON.stringify(todos), (err) => {
+      if(err) throw err;
+      res.status(201).json(newTodo);
+  })
+})
+});
+
+app.put('/todos/:id', (req, res) => {
+  fs.readFile(filePath, 'utf8', (err, data) => {
+    if(err) throw err;
+    const todos = JSON.parse(data);
+    const todoIndex = findIndex(todos, parseInt(req.params.id));
+    if(todoIndex === -1){
+      res.status(404).send();
+    }
+    else{
+      const updatedTodo = {
+      id : todos[todoIndex].id,
+      title: req.body.title,
+      description: req.body.description
+      }
+      todos[todoIndex] = updatedTodo;
+      fs.writeFile(filePath, JSON.stringify(todos), (err) => {
+        if(err) throw err;
+        res.json(updatedTodo);
+      });
+    }});
+  });
+
+
+  app.delete('/todos/:id', (req, res) => {
+    fs.readFile(filePath, 'utf8', (err, data) => {
+      if(err) throw err;
+      const todos = JSON.parse(data);
+      const todoIndex = findIndex(todos, pareseInt(req, res.params.id));
+      if(todoIndex === -1){
+        res.status(404).send();
+      }
+      else{
+       todos = removeIndex(todos, todoIndex);
+       fs.writeFile(filePath, Json.stringify(todos), (err) => {
+        if(err) throw err;
+        res.status(200).send();
+       })
+      }
+    })
+  })
+
+
+
+app.listen(port, () =>{
+  console.log(`Server is running on port ${port}.`);
+})
+
+app.use((req, res) =>{
+res.status(404).send();
+});
 
 module.exports = app;
diff --git a/02-nodejs/todos.json b/02-nodejs/todos.json
new file mode 100644
index 00000000..bd8d4c0f
--- /dev/null
+++ b/02-nodejs/todos.json
@@ -0,0 +1,12 @@
+[
+  { "name": "John Doe", "age": 30, "city": "New York" },
+  { "name": "Jane Smith", "age": 25, "city": "San Francisco" },
+  { "id": 872413, "title": "jbvbfib", "description": "khhvi" },
+  {
+    "id": 143363,
+    "title": "Sample Todo",
+    "description": "This is a updated  sample todo item."
+  },
+  { "id": 566104, "title": "", "description": "" },
+  { "id": 856526, "title": "", "description": "" }
+]