diff --git a/README.md b/README.md
index 0f9f073..88c484f 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,7 @@
-# Project API
+# 🧠 Projekt: Happy Thoughts API 
 
-This project includes the packages and babel setup for an express server, and is just meant to make things a little simpler to get up and running with.
+[Hola-Happy-Server](https://hola-happy-server.onrender.com)
 
-## Getting started
+[Hola-Happy-App](https://holahappythoughts.netlify.app/)
 
-Install dependencies with `npm install`, then start the server by running `npm run dev`
 
-## View it live
-
-Every project should be deployed somewhere. Be sure to include the link to the deployed project so that the viewer can click around and see what it's all about.
diff --git a/controllers/thoughtController.js b/controllers/thoughtController.js
new file mode 100644
index 0000000..532597b
--- /dev/null
+++ b/controllers/thoughtController.js
@@ -0,0 +1,186 @@
+import { Thought } from '../models/Thoughts.js';
+import mongoose from 'mongoose';
+
+export const listAllThoughts = async (req, res) => {
+  const sortBy = req.query.sortBy || 'createdAt';
+  const sortDir = req.query.sortDir === 'ascending' ? 1 : -1;
+
+  try {
+    const thoughts = await Thought.find()
+      .sort({ [sortBy]: sortDir })
+      .populate('createdBy', '_id email');
+    res.json(thoughts);
+  } catch (error) {
+    console.error('Mongoose error on listAllThoughts:', error);
+    res.status(500).json({ error: 'Could not fetch thoughts from database' });
+  }
+};
+
+export const getOneThought = async (req, res) => {
+  const { id } = req.params;
+
+  try {
+    let thought = await Thought.findById(id);
+
+    if (!thought) {
+      return res.status(404).json({
+        error: 'Thought not found',
+        requestedId: id,
+      });
+    }
+    thought = await thought.populate('createdBy', '_id email');
+    res.json(thought);
+  } catch (error) {
+    console.error('Mongoose error on getOneThought:', error);
+    res.status(400).json({ error: 'Invalid ID format or other error' });
+  }
+};
+
+export const addThought = async (req, res) => {
+  const { message } = req.body;
+
+  // Validate message length
+  if (!message || message.length < 4 || message.length > 140) {
+    return res.status(400).json({
+      error: 'Message is required and must be between 5 and 140 characters',
+    });
+  }
+
+  try {
+    const newThought = await Thought.create({
+      message,
+      createdBy: req.user._id,
+      // likes and createdAt will be set by defaults in the model
+    });
+
+    const populatedThought = await newThought.populate(
+      'createdBy',
+      '_id email'
+    );
+    res.status(201).json(populatedThought);
+  } catch (error) {
+    console.error('Mongoose error on addThought:', error);
+    if (error.name === 'ValidationError') {
+      res
+        .status(400)
+        .json({ error: 'Validation failed', details: error.errors });
+    } else {
+      res.status(400).json({ error: 'Could not add your thought' });
+    }
+  }
+};
+
+export const likeThought = async (req, res) => {
+  const { id } = req.params;
+  const userId = req.user?._id;
+
+  try {
+    const thought = await Thought.findById(id);
+
+    if (!thought) {
+      return res.status(404).json({ error: 'Thought not found' });
+    }
+
+    if (userId) {
+      const userIdStr = userId.toString();
+      // Convert likedBy to array of strings for logic
+      let likedByStrArr = thought.likedBy.map((id) => id.toString());
+      console.log('Before toggle:', { userIdStr, likedBy: likedByStrArr });
+      const hasLiked = likedByStrArr.includes(userIdStr);
+
+      if (hasLiked) {
+        likedByStrArr = likedByStrArr.filter((id) => id !== userIdStr);
+        console.log('User unliked. After removal:', likedByStrArr);
+      } else {
+        likedByStrArr.push(userIdStr);
+        console.log('User liked. After addition:', likedByStrArr);
+      }
+      thought.likes = likedByStrArr.length;
+      console.log('Final likedBy and likes:', {
+        likedBy: likedByStrArr,
+        likes: thought.likes,
+      });
+      // Convert likedBy back to ObjectIds before saving
+      thought.likedBy = likedByStrArr.map(
+        (id) => new mongoose.Types.ObjectId(id)
+      );
+
+      const updatedThought = await thought.save();
+      const populatedThought = await updatedThought.populate(
+        'createdBy',
+        '_id email'
+      );
+      return res.status(200).json(populatedThought);
+    }
+
+    // Guests should not be able to like
+    return res.status(401).json({ error: 'Authentication required to like' });
+  } catch (error) {
+    console.error('Error in likeThought:', error);
+    res
+      .status(500)
+      .json({ error: 'Could not toggle like', details: error.message });
+  }
+};
+
+export const updateThought = async (req, res) => {
+  const { id } = req.params;
+  const { message } = req.body;
+
+  try {
+    const thought = await Thought.findById(id);
+
+    if (!thought) {
+      return res.status(404).json({ error: 'Thought not found' });
+    }
+
+    // Kontrollera att den inloggade användaren äger tanken
+    if (thought.createdBy.toString() !== req.user._id.toString()) {
+      return res
+        .status(403)
+        .json({ error: 'You are not allowed to update this thought' });
+    }
+
+    thought.message = message;
+    const updatedThought = await thought.save();
+    const populatedThought = await updatedThought.populate(
+      'createdBy',
+      '_id email'
+    );
+    res.status(200).json(populatedThought);
+  } catch (err) {
+    res
+      .status(500)
+      .json({ error: 'Could not update thought', details: err.message });
+  }
+};
+
+export const removeThought = async (req, res) => {
+  const { id } = req.params;
+
+  try {
+    // Validate if the ID is a valid MongoDB ObjectId
+    if (!mongoose.Types.ObjectId.isValid(id)) {
+      return res.status(400).json({ error: 'Invalid thought ID format' });
+    }
+
+    const thought = await Thought.findById(id);
+
+    if (!thought) {
+      return res.status(404).json({ error: 'Thought not found' });
+    }
+
+    if (thought.createdBy.toString() !== req.user._id.toString()) {
+      return res
+        .status(403)
+        .json({ error: 'You are not allowed to delete this thought' });
+    }
+
+    await thought.deleteOne();
+    res.status(200).json({ message: 'Thought deleted successfully' });
+  } catch (err) {
+    res
+      .status(500)
+      .json({ error: 'Could not delete thought', details: err.message });
+  }
+};
diff --git a/controllers/userController.js b/controllers/userController.js
new file mode 100644
index 0000000..0231f90
--- /dev/null
+++ b/controllers/userController.js
@@ -0,0 +1,63 @@
+import User from '../models/Users.js';
+import bcrypt from 'bcrypt';
+import crypto from 'crypto';
+
+export const signup = async (req, res) => {
+  const { email, password } = req.body;
+
+  try {
+    if (!email || !password) {
+      return res.status(400).json({ error: 'Email and password are required' });
+    }
+    const existingUser = await User.findOne({ email });
+    if (existingUser) {
+      return res.status(400).json({ error: 'Email already exists' });
+    }
+    const salt = bcrypt.genSaltSync();
+    const hashedPassword = bcrypt.hashSync(password, salt);
+    const newUser = await new User({ email, password: hashedPassword }).save();
+    res.status(201).json({
+      email: newUser.email,
+      accessToken: newUser.accessToken,
+      id: newUser._id,
+    });
+  } catch (err) {
+    res
+      .status(500)
+      .json({ error: 'Internal server error', details: err.message });
+  }
+};
+
+export const login = async (req, res) => {
+  const { email, password } = req.body;
+
+  try {
+    const user = await User.findOne({ email });
+    if (!user) {
+      return res.status(401).json({ error: 'Invalid email or password' });
+    }
+    const passwordMatch = bcrypt.compareSync(password, user.password);
+    if (!passwordMatch) {
+      return res.status(401).json({ error: 'Invalid email or password' });
+    }
+    res.status(200).json({
+      email: user.email,
+      accessToken: user.accessToken,
+      id: user._id,
+    });
+  } catch (err) {
+    res
+      .status(500)
+      .json({ error: 'Internal server error', details: err.message });
+  }
+};
+
+export const logout = async (req, res) => {
+  try {
+    req.user.accessToken = crypto.randomBytes(64).toString('hex');
+    await req.user.save();
+    res.status(200).json({ message: 'Logged out successfully' });
+  } catch (err) {
+    res.status(500).json({ error: 'Could not log out', details: err.message });
+  }
+};
diff --git a/data.json b/data.json
deleted file mode 100644
index a2c844f..0000000
--- a/data.json
+++ /dev/null
@@ -1,121 +0,0 @@
-[
-    {
-    "_id": "682bab8c12155b00101732ce",
-    "message": "Berlin baby",
-    "hearts": 37,
-    "createdAt": "2025-05-19T22:07:08.999Z",
-    "__v": 0
-  },
-  {
-  "_id": "682e53cc4fddf50010bbe739",
-    "message": "My family!",
-    "hearts": 0,
-    "createdAt": "2025-05-22T22:29:32.232Z",
-    "__v": 0
-  },
-  {
-    "_id": "682e4f844fddf50010bbe738",
-    "message": "The smell of coffee in the morning....",
-    "hearts": 23,
-    "createdAt": "2025-05-22T22:11:16.075Z",
-    "__v": 0
-  },
-  {
-    "_id": "682e48bf4fddf50010bbe737",
-    "message": "Newly washed bedlinen, kids that sleeps through the night.. FINGERS CROSSED 🤞🏼\n",
-    "hearts": 6,
-    "createdAt": "2025-05-21T21:42:23.862Z",
-  "__v": 0
-  },
-  {
-    "_id": "682e45804fddf50010bbe736",
-    "message": "I am happy that I feel healthy and have energy again",
-    "hearts": 13,
-    "createdAt": "2025-05-21T21:28:32.196Z",
-    "__v": 0
-  },
-  {
-    "_id": "682e23fecf615800105107aa",
-    "message": "cold beer",
-    "hearts": 2,
-    "createdAt": "2025-05-21T19:05:34.113Z",
-    "__v": 0
-  },
-  {
-    "_id": "682e22aecf615800105107a9",
-    "message": "My friend is visiting this weekend! <3",
-    "hearts": 6,
-    "createdAt": "2025-05-21T18:59:58.121Z",
-    "__v": 0
-  },
-  {
-    "_id": "682cec1b17487d0010a298b6",
-    "message": "A god joke: \nWhy did the scarecrow win an award?\nBecause he was outstanding in his field!",
-    "hearts": 12,
-    "createdAt": "2025-05-20T20:54:51.082Z",
-  "__v": 0
-  },
-  {
-    "_id": "682cebbe17487d0010a298b5",
-    "message": "Tacos and tequila🌮🍹",
-    "hearts": 2,
-    "createdAt": "2025-05-19T20:53:18.899Z",
-    "__v": 0
-  },
-  {
-    "_id": "682ceb5617487d0010a298b4",
-    "message": "Netflix and late night ice-cream🍦",
-    "hearts": 1,
-    "createdAt": "2025-05-18T20:51:34.494Z",
-    "__v": 0
-  },
-  {
-    "_id": "682c99ba3bff2d0010f5d44e",
-    "message": "Summer is coming...",
-    "hearts": 2,
-    "createdAt": "2025-05-20T15:03:22.379Z",
-  "__v": 0
-  },
-  {
-    "_id": "682c706c951f7a0017130024",
-    "message": "Exercise? I thought you said extra fries! 🍟😂",
-    "hearts": 14,
-    "createdAt": "2025-05-20T12:07:08.185Z",
-    "__v": 0
-  },
-  {
-    "_id": "682c6fe1951f7a0017130023",
-    "message": "I’m on a seafood diet. I see food, and I eat it.",
-    "hearts": 4,
-    "createdAt": "2025-05-20T12:04:49.978Z",
-    "__v": 0
-  },
-  {
-    "_id": "682c6f0e951f7a0017130022",
-    "message": "Cute monkeys🐒",
-    "hearts": 2,
-    "createdAt": "2025-05-20T12:01:18.308Z",
-    "__v": 0
-  },
-  {
-    "_id": "682c6e65951f7a0017130021",
-    "message": "The weather is nice!",
-    "hearts": 0,
-    "createdAt": "2025-05-20T11:58:29.662Z",
-    "__v": 0
-  },
-  {
-    "_id": "682bfdb4270ca300105af221",
-    "message": "good vibes and good things",
-    "hearts": 3,
-    "createdAt": "2025-05-20T03:57:40.322Z",
-    "__v": 0
-  },
-  {
-    "_id": "682bab8c12155b00101732ce",
-    "message": "Berlin baby",
-    "hearts": 37,
-    "createdAt": "2025-05-19T22:07:08.999Z",
-    "__v": 0
-  }
-]
\ No newline at end of file
diff --git a/middlewares/authenticateUser.js b/middlewares/authenticateUser.js
new file mode 100644
index 0000000..cdfd1a6
--- /dev/null
+++ b/middlewares/authenticateUser.js
@@ -0,0 +1,28 @@
+import User from '../models/Users.js';
+
+const authenticateUser = async (req, res, next) => {
+  const authHeader = req.header('Authorization');
+
+  if (!authHeader || !authHeader.startsWith('Bearer ')) {
+    return res.status(401).json({ error: 'Missing or invalid token' });
+  }
+
+  const accessToken = authHeader.replace('Bearer ', '');
+
+  try {
+    const user = await User.findOne({ accessToken });
+
+    if (!user) {
+      return res.status(401).json({ error: 'Invalid token' });
+    }
+
+    req.user = user;
+    next();
+  } catch (err) {
+    res
+      .status(500)
+      .json({ error: 'Internal server error', details: err.message });
+  }
+};
+
+export default authenticateUser;
diff --git a/models/Thoughts.js b/models/Thoughts.js
new file mode 100644
index 0000000..4fab534
--- /dev/null
+++ b/models/Thoughts.js
@@ -0,0 +1,31 @@
+import mongoose from 'mongoose';
+
+const thoughtSchema = new mongoose.Schema({
+  message: {
+    type: String,
+    required: true,
+    minlength: 5,
+    maxlength: 140,
+  },
+  likes: {
+    type: Number,
+    default: 0,
+  },
+  likedBy: [
+    {
+      type: mongoose.Schema.Types.ObjectId,
+      ref: 'User',
+    },
+  ],
+  createdAt: {
+    type: Date,
+    default: () => new Date(), // ger dagens datum
+  },
+  createdBy: {
+    type: mongoose.Schema.Types.ObjectId,
+    ref: 'User',
+    required: false,
+  },
+});
+
+export const Thought = mongoose.model('Thought', thoughtSchema);
diff --git a/models/Users.js b/models/Users.js
new file mode 100644
index 0000000..a60aa73
--- /dev/null
+++ b/models/Users.js
@@ -0,0 +1,31 @@
+import mongoose from 'mongoose';
+import crypto from 'crypto';
+import bcrypt from 'bcrypt';
+
+const userSchema = new mongoose.Schema({
+  email: {
+    type: String,
+    required: true,
+    unique: true,
+    minlength: 3,
+  },
+  password: {
+    type: String,
+    required: true,
+    minlength: 6,
+  },
+  accessToken: {
+    type: String,
+    default: () => crypto.randomBytes(64).toString('hex'),
+  },
+  thoughts: [
+    {
+      type: mongoose.Schema.Types.ObjectId,
+      ref: 'Thought',
+    },
+  ],
+});
+
+const User = mongoose.model('User', userSchema);
+
+export default User;
diff --git a/package.json b/package.json
index bf25bb6..b26d4ef 100644
--- a/package.json
+++ b/package.json
@@ -2,18 +2,23 @@
   "name": "project-api",
   "version": "1.0.0",
   "description": "Project API",
+  "type": "module",
   "scripts": {
-    "start": "babel-node server.js",
-    "dev": "nodemon server.js --exec babel-node"
+    "start": "node server.js",
+    "dev": "nodemon server.js"
   },
   "author": "",
   "license": "ISC",
   "dependencies": {
-    "@babel/core": "^7.17.9",
-    "@babel/node": "^7.16.8",
-    "@babel/preset-env": "^7.16.11",
+    "bcrypt": "^6.0.0",
     "cors": "^2.8.5",
+    "dotenv": "^16.5.0",
     "express": "^4.17.3",
+    "express-list-endpoints": "^7.1.1",
+    "mongoose": "^8.15.1",
+    "uuid": "^11.1.0"
+  },
+  "devDependencies": {
     "nodemon": "^3.0.1"
   }
 }
diff --git a/routes/happyThoughtsRouter.js b/routes/happyThoughtsRouter.js
new file mode 100644
index 0000000..cc53fc8
--- /dev/null
+++ b/routes/happyThoughtsRouter.js
@@ -0,0 +1,23 @@
+import express from 'express';
+import authenticateUser from '../middlewares/authenticateUser.js';
+
+import {
+  listAllThoughts,
+  getOneThought,
+  addThought,
+  likeThought,
+  updateThought,
+  removeThought,
+} from '../controllers/thoughtController.js';
+
+const happyRouter = express.Router();
+
+//KOMIHÅG ATT URL börjar med /api/thoughts
+happyRouter.get('/', listAllThoughts);
+happyRouter.get('/:id', getOneThought);
+happyRouter.post('/', authenticateUser, addThought);
+happyRouter.post('/:id/likes', authenticateUser, likeThought);
+happyRouter.put('/:id', authenticateUser, updateThought);
+happyRouter.delete('/:id', authenticateUser, removeThought);
+
+export default happyRouter;
diff --git a/routes/userRoutes.js b/routes/userRoutes.js
new file mode 100644
index 0000000..e1bfae6
--- /dev/null
+++ b/routes/userRoutes.js
@@ -0,0 +1,14 @@
+import express from 'express';
+import bcrypt from 'bcrypt';
+import User from '../models/Users.js';
+import authenticateUser from '../middlewares/authenticateUser.js';
+import crypto from 'crypto';
+import { signup, login, logout } from '../controllers/userController.js';
+
+const userRoutes = express.Router();
+
+userRoutes.post('/signup', signup);
+userRoutes.post('/login', login);
+userRoutes.post('/logout', authenticateUser, logout);
+
+export default userRoutes;
diff --git a/server.js b/server.js
index f47771b..8422d69 100644
--- a/server.js
+++ b/server.js
@@ -1,22 +1,65 @@
-import cors from "cors"
-import express from "express"
+import cors from 'cors';
+import express from 'express';
+import expressListEndpoints from 'express-list-endpoints';
+import dotenv from 'dotenv';
+import mongoose from 'mongoose';
 
-// Defines the port the app will run on. Defaults to 8080, but can be overridden
-// when starting the server. Example command to overwrite PORT env variable value:
-// PORT=9000 npm start
-const port = process.env.PORT || 8080
-const app = express()
+import happyRouter from './routes/happyThoughtsRouter.js';
+import userRoutes from './routes/userRoutes.js';
 
-// Add middlewares to enable cors and json body parsing
-app.use(cors())
-app.use(express.json())
+// Ladda in .env-filen
+dotenv.config();
 
-// Start defining your routes here
-app.get("/", (req, res) => {
-  res.send("Hello Technigo!")
-})
+//moongoose
+const mongoUrl =
+  process.env.MONGO_URL || 'mongodb://127.0.0.1:27017/happyThoughts';
+mongoose
+  .connect(mongoUrl)
+  .then(() => {
+    console.log('Connected to MongoDB Atlas');
+  })
+  .catch((error) => {
+    console.error('MongoDB connection error:', error);
+  });
 
-// Start the server
+mongoose.connection.on('error', (error) => {
+  console.error('MongoDB connection error:', error);
+});
+
+const port = process.env.PORT || 8080;
+
+// Skapa en Express-app
+const app = express();
+
+// Middleware
+app.use(cors()); // Aktivera CORS
+app.use(express.json()); // Aktivera JSON-parsing
+
+// Rot-endpoint: lista alla endpoints requriement
+function ListEndpointsHandler(req, res) {
+  const endpoints = expressListEndpoints(app);
+  res.json(endpoints);
+}
+app.get('/', ListEndpointsHandler);
+
+//HappyRouter montering
+app.use('/api/thoughts', happyRouter);
+app.use('/', userRoutes);
+
+// Hantera 404
+app.use((req, res) => {
+  res.status(404).json({ error: 'Not Found' });
+});
+
+//Felhantering
+app.use((err, req, res, next) => {
+  console.error('💥 Server Error:', err);
+  res.status(err.status || 500).json({
+    error: err.message || 'Internal Server Error',
+  });
+});
+
+// Starta servern
 app.listen(port, () => {
-  console.log(`Server running on http://localhost:${port}`)
-})
+  console.log(`Server running on http://localhost:${port}`);
+});
diff --git a/testService.js b/testService.js
new file mode 100644
index 0000000..013f38e
--- /dev/null
+++ b/testService.js
@@ -0,0 +1,124 @@
+import assert from 'assert';
+
+import {
+  getAllThoughts,
+  getOneThought,
+  addThought,
+  incrementLike,
+  decrementLike,
+  updateThought,
+  removeThought,
+} from './services/thoughtService.js';
+
+////////////////////// ASSERT TESTING ////////////////////////
+
+// 1) Initial count
+const initialCount = getAllThoughts().length;
+
+// 2) Lägg till en ny thought
+const newThought = addThought({ message: 'Test thought' });
+assert.strictEqual(
+  getAllThoughts().length,
+  initialCount + 1,
+  `addThought: förväntade length ${initialCount + 1}, men fick ${
+    getAllThoughts().length
+  }`
+);
+
+// 3) Hämta just den thought
+const fetched = getOneThought(newThought._id);
+assert.ok(fetched, 'getOneThought: thought ska finnas');
+assert.strictEqual(
+  fetched.message,
+  'Test thought',
+  `getOneThought: förväntade message 'Test thought', men fick '${fetched.message}'`
+);
+
+// 4) Testa incrementLike
+incrementLike(newThought._id);
+assert.strictEqual(
+  getOneThought(newThought._id).hearts,
+  1,
+  'incrementLike: hearts borde vara 1'
+);
+
+// 5) Testa decrementLike (får inte gå under 0)
+decrementLike(newThought._id);
+assert.strictEqual(
+  getOneThought(newThought._id).hearts,
+  0,
+  'decrementLike: hearts borde vara tillbaka till 0'
+);
+decrementLike(newThought._id); // ytterligare en decrement
+assert.strictEqual(
+  getOneThought(newThought._id).hearts,
+  0,
+  'decrementLike: hearts borde inte gå under 0'
+);
+
+// 6) Testa updateThought
+updateThought(newThought._id, { message: 'Updated thought' });
+assert.strictEqual(
+  getOneThought(newThought._id).message,
+  'Updated thought',
+  'updateThought: message uppdaterades inte korrekt'
+);
+
+// 7) Testa removeThought
+const removed = removeThought(newThought._id);
+
+// 7.1) Förväntar oss ett objekt, inte bara true
+assert.ok(
+  removed && removed._id === newThought._id,
+  `removeThought: förväntade borttaget objekt med _id ${newThought._id}, men fick ${removed}`
+);
+
+// 7.2) Efter borttagningen ska getOneThought ge null
+assert.strictEqual(
+  getOneThought(newThought._id),
+  null,
+  'getOneThought: borde returnera null för borttagen thought'
+);
+
+// 7.3) Totalt antal ska ha minskat med 1 (till initialCount igen)
+assert.strictEqual(
+  getAllThoughts().length,
+  initialCount,
+  `removeThought: förväntade length ${initialCount}, men fick ${
+    getAllThoughts().length
+  }`
+);
+
+console.log('🎉 Alla service-tester gick igenom utan fel!');
+
+//////////////////////// MANUAL TESTING ////////////////////////
+
+// // 1) Börja med en ren mock-array
+// console.log('Initial:', getAllThoughts());
+
+// // 2) Lägg till en ny
+// const newT = addThought({ message: 'Testmeddelande' });
+// console.log('Efter add:', getAllThoughts());
+
+// // 3) Gilla och ogilla
+// incrementLike(newT._id);
+// console.log(
+//   '✅ Efter +1 like:',
+//   getAllThoughts().find((t) => t._id === newT._id)
+// );
+// decrementLike(newT._id);
+// console.log(
+//   ' ✅ Efter -1 like:',
+//   getAllThoughts().find((t) => t._id === newT._id)
+// );
+
+// // 4) Uppdatera
+// updateThought(newT._id, { message: 'Uppdaterat meddelande' });
+// console.log(
+//   ' ✅ Efter update:',
+//   getAllThoughts().find((t) => t._id === newT._id)
+// );
+
+// // 5) Ta bort
+// removeThought(newT._id);
+// console.log(' ✅ Efter remove:', getAllThoughts());