Hackrink

Hackrink is a personal Node.js playground designed to replicate the utility of HackerRank's JavaScript REPL locally. The repository keeps a pinned runtime, a fixed dependency set, and a collection of small runnable examples so it is easy to probe language behavior, compare library APIs, and experiment in a controlled environment that is close to an online coding sandbox.

Purpose

This repo exists to provide a lightweight local stand-in for the HackerRank JavaScript environment:

• quick feedback from small, self-contained scripts
• a stable and repeatable Node runtime
• a convenient place to try package behavior without scaffolding a full app
• a personal scratchpad for REPL-style experiments and coding challenge ideas

What this repo includes

• Runtime pinned to Node 20.15.1
• Package management pinned via Volta to npm 10.7.0
• Individual samples for HTTP clients, utility libraries, transpilation, and TypeScript
• One combined sample that exercises multiple installed packages together

The current dependency set includes:

• axios
• babel-cli and babel-preset-latest
• bignumber.js
• coffeescript
• jquery
• lodash
• node-fetch
• request
• typescript
• underscore

Prerequisites

• Node 20.15.1
• npm 10.7.0

If you use nvm, switch to the expected runtime with:

nvm use

If you use Volta, the pinned versions in package.json will be picked up automatically.

Install

npm install

Run the samples

Each sample is exposed as an npm script:

• Axios: npm run sample:axios
• Babel CLI: npm run sample:babel
• BigNumber: npm run sample:bignumber
• CoffeeScript: npm run sample:coffee
• node-fetch: npm run sample:fetch
• lodash: npm run sample:lodash
• request: npm run sample:request
• TypeScript: npm run sample:ts
• underscore: npm run sample:underscore
• Combined example: npm run sample:combo

The jQuery sample is browser-based rather than script-based:

open samples/jquery-example.html

Project structure

.
├── package.json
├── README.md
└── samples/
	├── axios-example.js
	├── babel-source.js
	├── babel-output.js
	├── bignumber-example.js
	├── coffeescript-example.coffee
	├── combined-example.js
	├── jquery-example.html
	├── lodash-example.js
	├── node-fetch-example.js
	├── request-example.js
	├── typescript-example.ts
	└── underscore-example.js

Notes

• This repository is a personal playground, not an application or publishable package.
• The samples are intentionally small so they can behave more like REPL probes than production code.
• Some dependencies here are intentionally older or legacy tools, which makes the repo useful for quick compatibility checks and API experiments.
• npm test is currently a placeholder and does not run an automated test suite.
• Yes, this is all based on a few GitHub Copilot prompts and minimal elbow grease. Get with the program. :)

License

MIT