freecodecamp / demo-projects

Example certification projects for our programming curriculum

Example Certification Projects

Responsive Web Design

• Tribute Page

  • Project Description
  • Example project

• Survey Form

  • Project Description
  • Example Project

• Product Landing Page

  • Project Description
  • Example Project

• Technical Documentation Page

  • Project Description
  • Example Project

• Personal Portfolio

  • Project Description
  • Example Project

JavaScript Algorithms and Data Structures

• Palindrome Checker

  • Project Description
  • Example project

• Roman Numeral Converter

  • Project Description
  • Example Project

• Telephone Number Validator

  • Project Description
  • Example Project

• Cash Register

  • Project Description
  • Example Project

• Pokémon Search App

  • Project Description
  • Example Project

Data Visualization

• Bar Chart

  • Project Description
  • Example Project

• Scatterplot Graph

  • Project Description
  • Example Project

• Heat Map

  • Project Description
  • Example Project

• Choropleth Map

  • Project Description
  • Example Project

• Treemap Diagram

  • Project Description
  • Example Project

APIs and Microservices

• Timestamp

  • Project description
  • Example project

• Request Header Parser

  • Project description
  • Example project

• URL Shortener

  • Project description
  • Example project

• Exercise Tracker

  • Project description
  • Example project

• File Metadata

  • Project description
  • Example project

Quality Assurance

• Metric-Imperial Converter

  • Project description
  • Example project

• Issue Tracker

  • Project description
  • Example project

• Personal Library

  • Project description
  • Example project

• Sudoku Solver

  • Project description
  • Example project

• American British Translator

  • Project description
  • Example project

Information Security

• Stock Price Checker

  • Project description
  • Example project

• Anonymous Message Board

  • Project description
  • Example project

• Secure Real Time Multiplayer Game

  • Project description
  • Example project

Coding Interview Prep

• Build a Pinterest Clone

  • Project description
  • Example project

• Chart the Stock Market

  • Project description
  • Landing page

• Image Search Abstraction Layer

  • Project description
  • Landing page

• P2P Video Chat Application

  • Project description
  • Example project

• Manage a Book Trading Club

  • Project description
  • Example project

• Voting App

  • Project description
  • Landing page

APIs and Proxies

Main Curriculum

• PokéAPI Proxy

  • Project description
  • Landing page

• Stock Price Checker Proxy

  • Project description
  • Landing page

Take Home Projects

• Build a freeCodeCamp Forum Homepage Proxy

  • Project description
  • Landing page

• Show the Local Weather API Proxy

  • Project description
  • Landing page

• Use the Twitch JSON API Proxy

  • Project description
  • Landing page

demo-projects's Issues

Configure Prettier, ESLint and Formatting Tools

Looking forward for reporting a security issue:
Please report security issues by following our security policy: https://contribute.freecodecamp.org/#/security

Describe the bug
Whenever I hit the "Format with Prettier" shortcut in Visual Studio Code; it seems like the entire file is set as changed rather than just the new lines of code.

To Reproduce
Steps to reproduce the behavior:

1. Open up the repository in Visual Studio Code
2. Click on the american-british-translator app folder
3. Open the server file
4. Format the document with Prettier
5. See error

Expected behavior
Only the lines I added should have been modified via Prettier.

Screenshots

Desktop (please complete the following information):

• OS: Windows 10
• Browser: FireFox
• Version: 119.0

Additional context
I would rather not add the endpoint for this app before this issue is resolved.

Format all the project files

A number of the files aren't properly formatted to the Prettier specifications. As mentioned in a previous PR, it will be wise to get around to it.

There's two different approaches we can take here. Either we do all of them at once, or we do it on a per project basis. And maybe see about adding a lint npm script.

Pros of full conversion in a single PR:

• All done in one fell swoop, and we won't realistically need to do it again

Cons:

• A lot of files to look at (200+)
• Take some time to look at

Create a liveliness endpoint for all apps

All the apps need to start with a base template, which should have a default liveliness check endpoint for deployments.

For instance, every app should implement a /status/ping, and that should return an HTTP error code of 200 with a response of { "msg" : "pong" }

This issue may be split into multiple PRs, with one PR for every project.

Tasks

Beta Give feedback

1. 25--5-clock (#486)
2. american-british-translator (#498)
3. anonymous-message-board (#512)
4. bar-chart (#513)
5. build-a-pinterest-clone (#514)
6. cash-register (#487)
7. chart-the-stock-market (#516)
8. choropleth-map (#517)
9. drum-machine (#488)
10. exercise-tracker (#518)
11. file-metadata-microservice (#499)
12. forum-proxy (#500)
13. heat-map (#525)
14. image-search-abstraction-layer (#526)
15. issue-tracker (#527)
16. javascript-calculator (#491)
17. manage-a-book-trading-club (#530)
18. markdown-previewer (#492)
19. metric-imperial-converter (#531)
20. nightlife-coordination-app (Note: we don't have an example app for this project)
21. p2p-video-chat-application (#529)
22. palindrome-checker (#495)
23. personal-library (#532)
24. personal-portfolio (#533)
25. pokeapi-proxy (#496)
26. pokemon-search-app (#534)
27. product-landing-page (#537)
28. random-quote-machine (#493)
29. request-header-parser-microservice (#540)
30. roman-numeral-converter (#539)
31. scatterplot-graph (#542)
32. secure-real-time-multiplayer-game (#503)
33. stock-price-checker-proxy (#507)
34. stock-price-checker (#543)
35. sudoku-solver (#544)
36. survey-form (#515)
37. technical-documentation-page (#546)
38. telephone-number-validator (#547)
39. timestamp-microservice (#524)
40. treemap-diagram (#548)
41. tribute-page (#494)
42. twitch-proxy (#522)
43. url-shortener-microservice (#523)
44. voting-app (#519)
45. weather-proxy (#511)

Cash Register Demo - floating-point error

Describe the bug
Demo of the Cash Register project has issue with the floating-point error. Causing it display values with error, and in certain situations, for remaining cash to go below $0.

To Reproduce

1. Go to https://cash-register.freecodecamp.rocks
2. Enter 330 and submit.
3. Enter 10 and submit.
4. Enter 4 and submit.
5. Enter 4 and submit.

At the step 3. value below status will include the number with clear floating-point error.
After step 5. in register Nickels are below $0.

Expected behavior
Cash shouldn't go below $0, or be displayed with more than a dozen of digits after the dot.

Screenshots

Additional context

• The least time-absorbing solution is adding toFixed(2) method to two more places:
  

  demo-projects/apps/cash-register/public/script.js

  Line 66 in a712591

  total -= denominations[i];

  
  

  demo-projects/apps/cash-register/public/script.js

  Line 70 in a712591

  result.change.push([reversedCid[i][0], count * denominations[i]]);

• More robust option is saying no to floats and changing more internals to not do calculations on floats.

Heruoku app - Build a Nightlife Coordination App no longer exists

Looking forward for reporting a security issue:
Please report security issues by following our security policy: https://contribute.freecodecamp.org/#/security

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Go to Build a Nightlife Coordination App project.
2. Click on https://yoyo44.herokuapp.com/
3. See app no longer exists

Expected behavior
There needs to be a new version in this repo.

Create GitHub Actions and Pipelines

25 + 5 Clock live demo project returns Status Code 526

Not sure if the redirect has anything to do with it.

https://25--5-clock.freecodecamp.rocks directs to https://clock.freecodecamp.rocks

---

Challenge: https://www.freecodecamp.org/learn/front-end-development-libraries/front-end-development-libraries-projects/build-a-25--5-clock

Additional context

Forum: https://forum.freecodecamp.org/t/error-on-project-build-a-25-5-clock/652475

Create Docker Registry

Use the DOCR private registry.

Bug: Example JavaScript Calculator accepts invalid input.

Describe the Issue

Example JavaScript Calculator accepts invalid input.

Affected Page

https://javascript-calculator.freecodecamp.rocks/

Your code

*2=

/2=

/2/2=

Expected behavior

It should ignore invalid input.

Screenshots

System

Device: Laptop OS: Windows 18.04.5 Browser: Chrome

Additional context

https://www.freecodecamp.org/learn/front-end-development-libraries/front-end-development-libraries-projects/build-a-javascript-calculator

Deploy Apps to Nomad-based Setup

We have refactored the repository to use a Docker-based setup for development and deployment. The current (legacy) version of the apps is live from the prod branch. The prod branch may receive selected hot patches as we work through the full migration.

Here is a task list for the same:

Tasks

Beta Give feedback

1. Create GitHub Actions and Pipelines #404
   +0
   
2. Create Docker Registry #405
   +0
   
3. ...

Note that the contributing guide will be updated eventually; if you are looking for instructions on working on the legacy version, please visit the guide on the prod branch.

Dependency Dashboard

This issue lists Renovate updates and detected dependencies. Read the Dependency Dashboard docs to learn more.

Pending Approval

These branches will be created by Renovate only once you click their checkbox below.

• chore(deps): update dependency @rollup/plugin-commonjs to v25
• chore(deps): update dependency @rollup/plugin-node-resolve to v15.2.3
• chore(deps): update dependency chart.js to v4
• chore(deps): update dependency concurrently to v8
• chore(deps): update dependency eslint-config-prettier to v9
• chore(deps): update dependency husky to v9
• chore(deps): update dependency marked to v12
• chore(deps): update dependency nodemon to v3
• chore(deps): update dependency prettier to v3
• chore(deps): update dependency prism to v9000
• chore(deps): update dependency rollup to v4
• chore(deps): update github actions to v4 (major) (actions/checkout, actions/setup-node)
• chore(deps): update node.js to v20
• chore(deps): update npm to v10
• fix(deps): update dependency @seald-io/nedb to v4
• fix(deps): update dependency chai to v5
• fix(deps): update dependency connect-mongo to v5
• fix(deps): update dependency dotenv to v16.4.5
• fix(deps): update dependency helmet to v7
• fix(deps): update dependency jsdom to v24
• fix(deps): update dependency mocha to v10
• fix(deps): update dependency mongodb to v6
• fix(deps): update dependency mongoose to v8
• fix(deps): update dependency winston-daily-rotate-file to v5
• fix(deps): update react monorepo to v18 (major) (react, react-dom)
• 🔐 Create all pending approval PRs at once 🔐

Rate-Limited

These updates are currently rate-limited. Click on a checkbox below to force their creation now.

• chore(deps): update dependency eslint-plugin-react to v7.34.1
• fix(deps): update babel monorepo (@babel/core, @babel/preset-env, @babel/preset-react)
• fix(deps): update dependency ejs to v3.1.10
• fix(deps): update dependency sanitize-html to v2.13.0
• fix(deps): update dependency winston to v3.13.0
• 🔐 Create all rate-limited PRs at once 🔐

Open

These updates have all been created already. Click a checkbox below to force a retry/rebase of any.

• chore(deps): update dependency axios to v1.6.8
• fix(deps): update dependency socket.io to v4.7.5
• chore(deps): update dependency d3 to v7.9.0
• chore(deps): update dependency marked to v2.1.3
• chore(deps): update dependency prism to v1.29.0
• Click on this checkbox to rebase all open PRs at once

Ignored or Blocked

These are blocked by an existing closed PR and will not be recreated unless you click a checkbox below.

• fix(deps): update dependency passport to v0.6.0 [security]
• fix(deps): update dependency node-fetch to v3.3.2
• chore(deps): update dependency @rollup/plugin-terser to v0.4.4
• chore(deps): update dependency eslint-config-prettier to v8.10.0

Detected dependencies

docker-compose

docker-compose.yml

• caddy 2.7.6

dockerfile

apps/anonymous-message-board/Dockerfile

• node 18-bullseye-slim

apps/build-a-pinterest-clone/Dockerfile

• node 18-bullseye-slim

apps/chart-the-stock-market/Dockerfile

• node 18-bullseye-slim

apps/exercise-tracker/Dockerfile

• node 18-bullseye-slim

apps/image-search-abstraction-layer/Dockerfile

• node 18-bullseye-slim

apps/issue-tracker/Dockerfile

• node 18-bullseye-slim

apps/manage-a-book-trading-club/Dockerfile

• node 18-bullseye-slim

apps/personal-library/Dockerfile

• node 18-bullseye-slim

apps/pokeapi-proxy/Dockerfile

• node 18-bullseye-slim

apps/stock-price-checker-proxy/Dockerfile

• node 18-bullseye-slim

apps/stock-price-checker/Dockerfile

• node 18-bullseye-slim

apps/twitch-proxy/Dockerfile

• node 18-bullseye-slim

apps/url-shortener-microservice/Dockerfile

• node 18-bullseye-slim

apps/voting-app/Dockerfile

• node 18-bullseye-slim

apps/weather-proxy/Dockerfile

• node 18-bullseye-slim

shared.Dockerfile

• node 18-bullseye-slim

github-actions

.github/workflows/node-ci.yml

• actions/checkout v2@ee0669bd1cc54295c223e0bb666b733df41de1c5
• actions/setup-node v2@7c12f8017d5436eb855f1ed4399f037a36fbd9e8

html

apps/25--5-clock/index.html

• react 18.2.0
• react-dom 18.2.0

apps/bar-chart/index.html

• d3 7.8.5

apps/build-a-pinterest-clone/views/index.html

• jquery 3.7.1

apps/chart-the-stock-market/public/index.html

• socket.io 4.7.2
• Chart.js 2.9.4

apps/choropleth-map/index.html

• d3 7.8.5
• topojson 3.0.2

apps/heat-map/index.html

• d3 7.8.5

apps/markdown-previewer/index.html

• prism 1.23.0
• marked 2.0.3
• prism 1.23.0

apps/random-quote-machine/index.html

• jquery 3.7.1
• jqueryui 1.13.2

apps/scatterplot-graph/index.html

• d3 7.8.5

apps/treemap-diagram/index.html

• d3 7.8.5

npm

apps/25--5-clock/package.json

• dotenv 16.0.0
• express 4.19.2
• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/preset-react 7.23.3
• @rollup/plugin-babel 6.0.4
• @rollup/plugin-commonjs 23.0.7
• @rollup/plugin-node-resolve 15.0.1
• @rollup/plugin-replace 5.0.5
• @rollup/plugin-terser 0.2.0
• rollup 2.79.1

apps/american-british-translator/package.json

• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/register 7.23.7
• body-parser 1.20.2
• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• mocha 9.2.2

apps/anonymous-message-board/package.json

• body-parser 1.20.2
• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• helmet 3.23.3
• mocha 9.2.2
• mongodb 3.7.4
• sanitize-html 2.12.1

apps/bar-chart/package.json

• dotenv 16.0.0
• express 4.19.2

apps/build-a-pinterest-clone/package.json

• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/preset-react 7.23.3
• @rollup/plugin-babel 6.0.4
• @rollup/plugin-commonjs 21.1.0
• @rollup/plugin-node-resolve 13.3.0
• @rollup/plugin-replace 5.0.5
• body-parser 1.20.2
• connect-mongo 3.2.0
• dotenv 14.3.2
• express 5.0.0-beta.3
• express-session 1.18.0
• mongoose 5.13.22
• passport 0.5.2
• passport-github 1.1.0
• react 15.7.0
• react-dom 15.7.0
• react-masonry-component 6.3.0
• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/preset-react 7.23.3
• @rollup/plugin-babel 6.0.4
• @rollup/plugin-commonjs 23.0.7
• @rollup/plugin-node-resolve 15.0.1
• @rollup/plugin-replace 5.0.5
• @rollup/plugin-terser 0.2.0
• concurrently 7.6.0
• nodemon 2.0.22
• rollup 2.79.1

apps/cash-register/package.json

• dotenv 16.0.0
• express 4.19.2

apps/chart-the-stock-market/package.json

• dotenv 14.3.2
• express 4.19.2
• socket.io 4.7.2

apps/choropleth-map/package.json

• dotenv 16.0.0
• express 4.19.2

apps/drum-machine/package.json

• dotenv 16.0.0
• express 4.19.2
• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/preset-react 7.23.3
• @rollup/plugin-babel 6.0.4
• @rollup/plugin-commonjs 23.0.7
• @rollup/plugin-node-resolve 15.0.1
• @rollup/plugin-replace 5.0.5
• @rollup/plugin-terser 0.2.0
• rollup 2.79.1

apps/exercise-tracker/package.json

• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• mocha 9.2.2
• mongodb 3.7.4
• mongoose 5.13.22

apps/file-metadata-microservice/package.json

• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 5.0.0-beta.3
• mocha 9.2.2
• multer 1.4.4

apps/forum-proxy/package.json

• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• mocha 9.2.2
• node-fetch 3.3.1

apps/heat-map/package.json

• dotenv 16.0.0
• express 4.19.2

apps/image-search-abstraction-layer/package.json

• dotenv 14.3.2
• express 4.19.2
• google-images 2.1.0
• moment 2.30.1
• mongodb 3.7.4

apps/issue-tracker/package.json

• body-parser 1.20.2
• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• mocha 9.2.2
• mongodb 3.7.4
• mongoose 5.13.22

apps/javascript-calculator/package.json

• dotenv 16.0.0
• express 4.19.2
• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/preset-react 7.23.3
• @rollup/plugin-babel 6.0.4
• @rollup/plugin-commonjs 23.0.7
• @rollup/plugin-node-resolve 15.0.1
• @rollup/plugin-replace 5.0.5
• @rollup/plugin-terser 0.2.0
• rollup 2.79.1

apps/manage-a-book-trading-club/package.json

• body-parser 1.20.2
• connect-flash 0.1.1
• connect-mongo 3.2.0
• cookie-parser 1.4.6
• dotenv 14.3.2
• express 4.19.2
• express-session 1.18.0
• font-awesome 4.7.0
• helmet 3.23.3
• mongoose 5.13.22
• morgan 1.10.0
• passport 0.5.2
• passport-github 1.1.0
• pug 3.0.2
• chai 4.4.1
• chai-as-promised 7.1.1
• chai-dom 1.12.0
• chai-http 4.4.0
• mocha 9.2.2

apps/markdown-previewer/package.json

• dotenv 16.0.0
• express 4.19.2
• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/preset-react 7.23.3
• @rollup/plugin-babel 6.0.4
• @rollup/plugin-commonjs 23.0.7
• @rollup/plugin-node-resolve 15.0.1
• @rollup/plugin-replace 5.0.5
• @rollup/plugin-terser 0.2.0
• rollup 2.79.1

apps/metric-imperial-converter/package.json

• body-parser 1.20.2
• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• mocha 9.2.2

apps/p2p-video-chat-application/package.json

• dotenv 14.3.2
• express 4.19.2
• jquery 3.7.1
• simple-peer 9.11.1
• socket.io 4.7.2
• @rollup/plugin-commonjs 21.1.0
• @rollup/plugin-node-resolve 13.3.0
• @rollup/plugin-terser 0.2.0
• concurrently 7.6.0
• nodemon 2.0.22
• rollup 2.79.1

apps/palindrome-checker/package.json

• dotenv 16.0.0
• express 4.19.2

apps/personal-library/package.json

• body-parser 1.20.2
• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• mocha 9.2.2
• mongodb 3.7.4
• mongoose 5.13.22

apps/personal-portfolio/package.json

• dotenv 16.0.0
• express 4.19.2

apps/pokeapi-proxy/package.json

• axios 1.6.7
• cors 2.8.5
• dotenv 16.3.1
• express 4.19.2
• node-cache 5.1.2

apps/pokemon-search-app/package.json

• dotenv 16.0.0
• express 4.19.2

apps/product-landing-page/package.json

• dotenv 16.0.0
• express 4.19.2

apps/random-quote-machine/package.json

• dotenv 16.0.0
• express 4.19.2

apps/request-header-parser-microservice/package.json

• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 5.0.0-beta.3
• mocha 9.2.2

apps/roman-numeral-converter/package.json

• dotenv 16.0.0
• express 4.19.2

apps/scatterplot-graph/package.json

• dotenv 16.0.0
• express 4.19.2

apps/secure-real-time-multiplayer-game/package.json

• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/register 7.23.7
• body-parser 1.20.2
• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• helmet 3.23.3
• jsdom 16.7.0
• mocha 9.2.2
• socket.io 4.7.2

apps/stock-price-checker-proxy/package.json

• @seald-io/nedb 2.2.2
• axios 1.6.7
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2

apps/stock-price-checker/package.json

• body-parser 1.20.2
• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• helmet 3.23.3
• mocha 9.2.2
• mongodb 3.7.4
• request 2.88.2

apps/sudoku-solver/package.json

• @babel/core 7.24.0
• @babel/preset-env 7.24.0
• @babel/register 7.23.7
• body-parser 1.20.2
• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• jsdom 16.7.0
• mocha 9.2.2

apps/survey-form/package.json

• dotenv 16.0.0
• express 4.19.2

apps/technical-documentation-page/package.json

• dotenv 16.0.0
• express 4.19.2

apps/telephone-number-validator/package.json

• dotenv 16.0.0
• express 4.19.2

apps/timestamp-microservice/package.json

• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• mocha 9.2.2

apps/treemap-diagram/package.json

• dotenv 16.0.0
• express 4.19.2

apps/tribute-page/package.json

• dotenv 16.0.0
• express 4.19.2

apps/twitch-proxy/package.json

• @seald-io/nedb 2.2.2
• cors 2.8.5
• dotenv 14.3.2
• express 5.0.0-beta.3
• node-cron 3.0.3
• node-fetch 3.3.0
• request 2.88.2
• winston 3.12.0
• winston-daily-rotate-file 3.10.0

apps/url-shortener-microservice/package.json

• chai 4.4.1
• chai-http 4.4.0
• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• mocha 9.2.2
• mongoose 5.13.22

apps/voting-app/package.json

• body-parser 1.20.2
• dotenv 14.3.2
• ejs 3.1.9
• express 4.19.2
• mongodb 3.7.4

apps/weather-proxy/package.json

• cors 2.8.5
• dotenv 14.3.2
• express 4.19.2
• request 2.88.2

package.json

• dotenv ^16.0.3
• @types/jest ^29.5.10
• axios 1.6.0
• eslint-config-prettier 8.7.0
• eslint-plugin-react 7.34.0
• husky 8.0.3
• jest 29.7.0
• lint-staged 15.2.2
• prettier 2.8.8
• node 18
• npm 9

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Bug: cash register app has malformed html

Looking forward for reporting a security issue:
Please report security issues by following our security policy: https://contribute.freecodecamp.org/#/security

Describe the bug
The opening main tag in the file is never closed. As a result, it complains about the body closing tag is unexpected.

To Reproduce
Steps to reproduce the behavior:

1. Open `apps/cash-register/index.html"
2. Open the finder tool
3. Look for <main>
4. See error

Expected behavior
The main tag should be closed.

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Windows 10
• Browser: Firefox
• Version: 119.0.1

Additional context
I discovered this while I was reformatting the existing code in the repositories.

Create GitHub Actions workflow to build and test all the apps

When we update applications like automated package updates, we want to run tests and check if they are passing before merging PRs.

Tests could be as minimal as checking the health status endpoints created in #484 to more expanded versions where we run some unit or browser-based testing.

This issue may be split into multiple PRs, with one PR for every project.

Tasks

Beta Give feedback

1. 25--5-clock
2. american-british-translator
3. anonymous-message-board
4. bar-chart
5. build-a-pinterest-clone
6. cash-register
7. chart-the-stock-market
8. choropleth-map
9. drum-machine
10. exercise-tracker
11. file-metadata-microservice
12. forum-proxy
13. heat-map
14. image-search-abstraction-layer
15. issue-tracker
16. javascript-calculator
17. manage-a-book-trading-club
18. markdown-previewer
19. metric-imperial-converter
20. nightlife-coordination-app
21. p2p-video-chat-application
22. palindrome-checker
23. personal-library
24. personal-portfolio
25. pokeapi-proxy
26. pokemon-search-app
27. product-landing-page
28. random-quote-machine
29. request-header-parser-microservice
30. roman-numeral-converter
31. scatterplot-graph
32. secure-real-time-multiplayer-game
33. stock-price-checker-proxy
34. stock-price-checker
35. sudoku-solver
36. survey-form
37. technical-documentation-page
38. telephone-number-validator
39. timestamp-microservice
40. treemap-diagram
41. tribute-page
42. twitch-proxy
43. url-shortener-microservice
44. voting-app
45. weather-proxy