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React and Next.js: build modern web applications

Two live React and Next.js applications in your portfolio

  • 24 h of training
  • 8 modules · 40 lessons
  • 97 exercises
  • 8 projects
  • Certificate included

What you will be able to do

  • React interface development (components, props, hooks, controlled forms)
  • React state management (useState, useReducer, Context, custom hooks)
  • Next.js App Router (routing, Server Components, Server Actions, Route Handlers)
  • Data validation with Zod and session-based authentication
  • Automated testing with Vitest and Testing Library
  • Core Web Vitals optimization and deployment to Vercel or a VPS

What you will produce

  • A restaurant menu broken down into React components
  • An interactive cart with a total, delivery fees and derived state
  • A validated order form with submission states
  • A menu loaded from an API with custom hooks
  • A complete ordering application with a persistent global cart
  • A multi-page Next.js website with SEO and dynamic pages
  • Appointment booking with Server Actions and a protected admin area
  • The booking application tested, optimized and live, with its portfolio README

Possible earnings

A junior React and Next.js developer can charge 400,000 to 1,200,000 FCFA (about $670 to $2,000) for an ordering or booking application for a small business in Dakar or Abidjan, or aim for an internship and then a first job paying 200,000 to 400,000 FCFA (about $330 to $670) a month in Dakar in 2026, up to 500,000 FCFA (about $830) at a fast-growing startup (projects with a database, payments and an API belong to level 5).

Indicative estimate, depending on your market, pace and work. No income is guaranteed.

Tools used

  • React 19
  • Next.js 15
  • Vite
  • Node 22 and npm
  • Zod
  • Vitest
  • Testing Library
  • Lighthouse
  • Vercel
  • Git and GitHub

What you'll learn

  • Break an interface down into reusable React components with props and children
  • Manage local state, events and derived state without mutating data
  • Build controlled forms with validation and helpful error messages
  • Load data with proper loading and error handling, and write custom hooks
  • Organize global state with useReducer and Context, persisted in the browser
  • Build a Next.js App Router application with Server Components, Server Actions and protected pages
  • Test, optimize and deploy a Next.js application to production

Prerequisites

  • Level 3 of the track (JavaScript: make a website come alive and interactive) recommended, or solid command of functions, arrays, objects, the DOM, ES modules and fetch
  • HTML and CSS basics (level 2 or equivalent)
  • A computer with Node 22, VS Code, Git and Google Chrome
  • 4 to 5 hours a week for 5 to 6 weeks

About this course

## Go from scripts that manipulate the DOM to applications you deliver to clients In Dakar as in Abidjan, small businesses no longer ask only for a showcase website. They want online ordering, appointment booking, an admin area, a dashboard. Today these applications are built with React and Next.js. This course teaches you to write them cleanly, test them and put them online. ### Who this course is for - You completed level 3 (JavaScript: make a website come alive and interactive) or you are already comfortable with functions, arrays, objects, the DOM and `fetch`. - You want to move to a professional tool, the one internship and freelance job posts ask for. - You are a freelancer and you want to sell applications, not just pages. ### What you do during the course - You break an interface down into React components and handle state, events and validated forms. - You load data, write your own hooks and organize global state with `useReducer` and Context. - You move to Next.js: the App Router, Server Components, metadata and SEO. - You process forms on the server with Server Actions and Zod, and you protect an admin area. - You test your logic with Vitest and Testing Library, measure performance and deploy. ### What you leave with Two complete applications: online ordering for a restaurant in Thiès built with React, then a booking application for a beauty salon in Dakar built with Next.js, tested and live. Every module produces a portfolio deliverable. ### Your place in the Web Development track This is level 4: after level 3 (JavaScript: make a website come alive and interactive) and before level 5 (Full-Stack JavaScript Developer), which adds the database, the API, payments and a complete portfolio.

Who it is for: Junior developers who know the JavaScript basics (functions, arrays, the DOM, fetch), computer science students, front-end integrators and freelancers in Dakar, Thiès, Abidjan, Bamako, Cotonou or the diaspora who want to ship modern web applications with React and Next.js.

Curriculum

A module-by-module path: lessons, exercises, quizzes and projects to submit.

  1. Module 1· 12 exercises

    Getting started with React: components, JSX and props

    You create your first React project with Vite and break a restaurant menu down into reusable components.

    • Why React: from hand-written DOM code to componentsFree preview18 min
    • Create the project with Vite and write JSXFree preview20 min
    • Props: reusable componentsFree preview20 min
    • Composing a page: children, simple lists and stylesFree preview20 min
    • Module handout (PDF)Free preview5 min
    • Quiz: components, JSX and propsModule quiz
    • The Chez Fatou menu as React componentsProject to submit
  2. Module 2· 13 exercises

    State and events: making the interface interactive

    You give your components a memory with useState, respond to clicks and build a cart whose total calculates itself.

    • useState: a component's memory20 min
    • Handling events and updating without mutation20 min
    • Lifting state up: sharing data between components18 min
    • Derived state: calculate instead of storing18 min
    • Module handout (PDF)5 min
    • Quiz: state and eventsModule quiz
    • The Chez Fatou interactive cartProject to submit
  3. Module 3· 12 exercises

    Lists, forms and validation

    You display filtered and sorted lists, build a controlled order form and validate it before it is submitted.

    • Displaying, filtering and sorting lists with stable keys18 min
    • Controlled forms: inputs, dropdowns and checkboxes20 min
    • Validating input: phone numbers, required fields and error messages20 min
    • Submitting cleanly: pending states, double-click protection and confirmation18 min
    • Module handout (PDF)5 min
    • Quiz: lists and formsModule quiz
    • The validated order formProject to submit
  4. Module 4· 12 exercises

    Effects, data and custom hooks

    You load data from an API with loading, error and cancellation handling, then move that logic into your own hooks.

    • useEffect: syncing a component with the outside world20 min
    • Loading data: loading, error and empty states20 min
    • Writing your own hooks: useFetch and useLocalStorage20 min
    • useRef, useMemo and the effects you don't need18 min
    • Module handout (PDF)5 min
    • Quiz: effects and hooksModule quiz
    • The daily menu loaded from an APIProject to submit
  5. Module 5· 12 exercises

    Global state and React application architecture

    You centralize state transitions with useReducer, share the cart with Context and organize the project so it holds up over time.

    • useReducer: centralizing state transitions20 min
    • Context: sharing state without prop drilling18 min
    • A persistent global cart: reducer, Context and localStorage20 min
    • Organizing folders and choosing a state library18 min
    • Module handout (PDF)5 min
    • Quiz: global state and architectureModule quiz
    • The complete Chez Fatou ordering applicationProject to submit
  6. Module 6· 12 exercises

    Next.js: the App Router, server rendering and SEO

    You move to Next.js: file-based routes, layouts, Server and Client Components, data loaded on the server and metadata for Google.

    • From React to Next.js: why server rendering matters18 min
    • File-based routing, layouts and dynamic routes20 min
    • Server Components, Client Components and data fetching20 min
    • Metadata, images and SEO for a Next.js application18 min
    • Module handout (PDF)5 min
    • Quiz: the Next.js App RouterModule quiz
    • The Awa Beauté salon website in Next.jsProject to submit
  7. Module 7· 12 exercises

    Server Actions, server-side validation and authentication

    You process forms on the server with Server Actions and Zod, expose an API with a Route Handler and protect the admin area.

    • Server Actions: handling a form without writing an API20 min
    • Validating on the server with Zod and returning errors to the form20 min
    • Route Handlers: exposing a clean API18 min
    • Authentication: sessions, middleware and protected pages22 min
    • Module handout (PDF)5 min
    • Quiz: Server Actions and authenticationModule quiz
    • Online booking and the manager's areaProject to submit
  8. Module 8· 12 exercises

    Testing, performance and going to production

    You test logic and components, measure and improve performance on mobile, then deploy the application and present it in your portfolio.

    • Testing logic with Vitest20 min
    • Testing components with Testing Library20 min
    • Performance: Core Web Vitals, JavaScript weight and mobile networks18 min
    • Deploying: Vercel or a VPS, environment variables and a delivery checklist20 min
    • Module handout (PDF)5 min
    • Quiz: testing, performance and deploymentModule quiz
    • Final project: the Awa Beauté application, tested and liveCapstone
  9. Certificate included

Your certificate at the end

A numbered certificate with your validated skills, a public page and a verification QR code. Add it to LinkedIn in one click.

Kolonell Academy
Verified by Kolonell Academy

Certificate of skills

Your name

has completed and validated the course

React and Next.js: build modern web applications

Certified skills

  • React interface development (components, props, hooks, controlled forms)
  • React state management (useState, useReducer, Context, custom hooks)
  • Next.js App Router (routing, Server Components, Server Actions, Route Handlers)
  • Data validation with Zod and session-based authentication
  • Automated testing with Vitest and Testing Library
  • Core Web Vitals optimization and deployment to Vercel or a VPS

Number KOL-CERT-2026-XXXXX

Mohamed Bah

Founder, Kolonell Academy

Poster for React and Next.js: build modern web applications

Course poster

Download the poster to print it, send it to your employer or share it with colleagues. The full programme details every module.

This course is part of the track

Développement web

Level 4 of 5 · Career

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
See the 5 track levels

Next level · 5/5 Pro Track

Full-Stack JavaScript Developer

Senior level, projects and leadership

Your full-stack app live online and 8 projects on GitHub by the end of the track

200,000 FCFA 45 h

View the next level

Your instructor

Mohamed Bah

PhD in computer science and founder of Kolonell, a digital agency and platform based in Dakar. He designs and deploys websites and web applications for SMEs in Senegal, Côte d'Ivoire and the diaspora, using the tools taught in this track: React, Next.js, Node and Git.

Questions about this course

Do I need to have completed level 3?

It is recommended. If you can already write functions, use map and filter, manipulate the DOM and call an API with fetch, you can start right here.

Why React and Next.js rather than Vue or Angular?

React is the most requested library in internship and freelance job posts in French-speaking Africa and in Europe in 2026, and Next.js is the most widely used framework for shipping it to production. The concepts you learn (components, state, server rendering) carry over to Vue or Svelte later.

My computer is old. Is it good enough?

A computer with 8 GB of RAM runs Vite and Next.js in development without trouble. With 4 GB, close Chrome during builds and stick with Vite for modules 1 to 5.

Do I need to know TypeScript?

No. Modules 1 to 5 are in JavaScript. From module 6 on, the Next.js examples use light TypeScript, explained as you go: types for props and objects, nothing more.

Are the coding exercises graded?

Yes. Exercises on logic (cart calculations, validation, reducers, helpers) are tested automatically in the browser. React and Next.js specific concepts are checked through questions and the end-of-module projects.

How much time per week?

Plan for 4 to 5 hours a week for 5 to 6 weeks, projects included. The final project alone takes about 4 hours.

How do I pay?

Via Wave or Orange Money. After enrolling you receive a pro forma invoice by email with the number to pay. Send the proof on WhatsApp: your access is activated within 24 business hours.

How long do I keep access?

For life, updates included. Learn at your own pace and revisit lessons as often as you need.

How do I get the certificate?

Complete the lessons and pass each module quiz with at least 70%. The certificate is generated automatically, with a unique number and a public verification page.

Our commitments

  • Lifetime access, updates included
  • Publicly verifiable certificate
  • Wave / Orange Money payment, activation within 24 business hours
  • WhatsApp support

100,000 FCFA · 152 €

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