Full Stack Open – University of Helsinki

This repository contains all the exercises and projects I have developed to complete the Full Stack Open course at the University of Helsinki. The program is geared toward modern web development with JavaScript, focusing on single-page applications (SPAs) implemented with React and backed by RESTful web services created with Node.js.

Throughout the course, I have worked on building complete applications that integrate frontend, backend, and databases, following best practices in development, testing, and deployment.

Main technologies used:

• React
• Redux
• React Query and Context
• React Router
• Modern JavaScript
• Node.js and Express
• MongoDB and Mongoose
• RESTful APIs
• Authentication and authorization with JWT
• Testing with Vitest
• End-to-end testing with Playwright
• CSS and style frameworks (React Bootstrap, Material UI, Tailwind CSS, styled-components)
• Vite and Webpack
• ESLint
• Git and GitHub
• Custom hooks
• Application deployment

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Why is this course relevant?

• It is one of the most up-to-date programs in modern web development.
• It teaches the most in-demand stack today.
• It includes unit testing, integration, end-to-end testing, and cloud deployment.
• It is based on real projects that integrate frontend, backend, and databases.

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Prerequisites

• Good programming skills.
• Basic knowledge of web programming and databases.
• Basic knowledge of Git and version control.
• Perseverance and the ability to solve problems and search for information independently.

In addition, fluency in a programming language is recommended, which usually requires 100–200 hours of practice beforehand.

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Progress and achievements

This repository contains the complete course (Parts 0 to 7) with all my projects completed to finish the exercises (138 exercises in total).
Result:

• Full Stack Open Certificate – View certificate
• Highest grade: Grade 5
• Credits earned: 7 ECTS
• Total workload: ~145 hours

Official course information

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Content by sections

Part 0 – Fundamentals of web development

This part provides an overview of the basic concepts of web development and analyzes advances in web application development over the last few decades.

See Part 0
Total hours: 6

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Part 1 – Introduction to React and JavaScript

The React library for building interfaces in the browser is introduced.
Key features of JavaScript necessary for working with React are also reviewed:

• Components
• Event handlers
• State management
• Application debugging

See Part 1
Total hours: 15

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Part 2 – Advancing in React and connecting to the backend

You will learn how to:

• Represent data collections
• Manage forms in React
• Obtain and manage data from a remote backend server
• Style components with CSS

See Part 2
Total hours: 15

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Part 3 – Backend with Node.js and MongoDB

Implementation of a REST API using Node.js + Express, with storage in MongoDB.

• Data validation
• Error handling
• Deployment of the application on the internet
• Use of ESLint to maintain code quality

See Part 3
Total hours: 22

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Part 4 – Testing and authentication in the backend

• Unit and integration testing for the backend
• Token-based authentication and authorization (JWT)
• User management with Mongoose
• Use of async/await and error handling

See Part 4
Total hours: 20

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Part 5 – Frontend testing and authentication

We return to the frontend to:

• Implement token-based authentication
• Save and manage the token in local storage
• Use props.children and PropTypes
• Unit testing with Vitest
• Integration testing
• E2E testing with Playwright

See Part 5
Total hours: 25

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Part 6 – Advanced state management

• Flux pattern and Redux library
• Redux Toolkit
• Using multiple reducers and communicating with the server
• Global state management with React Query and React Context
• Using Redux to communicate with the server
• useReducer hook

See Part 6
Total hours: 20

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Part 7 – React Router, Hooks, and advanced styles

• Using React Router for navigation and dynamic routes
• Creating custom hooks
• Styles with fram

See Part 7
Total hours: 22