# JavaScript Code Challenges: Curated Interview Problems for All Skill Levels > A free, MIT-licensed collection of modern JavaScript interview challenges published at jscodechallenges.vercel.app. It targets interviewees, interviewers, and developers running self-assessments, but the sparse README leaves coverage and difficulty structure undocumented. **sadanandpai/javascript-code-challenges** — A collection of JavaScript modern interview code challenges for beginners to experts - Repository: https://github.com/sadanandpai/javascript-code-challenges - Website: https://jscodechallenges.vercel.app - Stars: 4,462 · Forks: 854 - Language: MDX - License: MIT - Published: 2026-09-23 · Updated: 2026-09-23 · Language: en - Canonical page: https://hysenlabs.com/projects/sadanandpai-javascript-code-challenges ## Who This Collection Serves and What It Offers JavaScript interviews regularly include practical coding problems: closures, prototype chains, async patterns, array manipulation, and modern ES6 syntax. Preparing for those questions requires a source of real problems. JavaScript Code Challenges is a repository of modern interview challenges collected and published by Sadanand Pai under the MIT license. The README describes its audience directly: interviewees preparing for technical screens, interviewers who need a bank of problems to draw from, anyone doing a knowledge test, and developers who want practice material. The description names four distinct groups, which means the collection is not scoped to a single preparation style. The challenges target a range from beginners to experts. An interviewer running a senior-level round and a developer reviewing ES6 features for the first time both have a stated place in the intended audience. That breadth is unusual for a collection of this type. It does mean the collection carries problems across a wide difficulty spread, which can be useful or unfocused depending on what a reader needs. The website at jscodechallenges.vercel.app is the primary access point. Every challenge is readable in a browser without cloning the repository or installing any tooling. ## How MDX Structures Each Challenge The repository lists MDX as its primary language. MDX combines Markdown prose with JSX components. In a challenge collection, this means each problem file can carry a written problem statement, constraints, and expected output alongside React components the web application renders interactively. This format separates concern clearly. Challenge authors write MDX files. The web application in the web/ directory reads those files and displays them as web pages deployed to Vercel. The result is that someone adding a challenge edits only an MDX file; the presentation layer handles the rest. The top-level directory listing confirms this split: .github/ for project metadata, CODE_OF_CONDUCT.md, LICENSE, README.md, contributing.md, usageGuide.md, and web/ for the application. The usageGuide.md file exists at the root, though the README does not reproduce its contents. Its presence indicates that conventions for reading or writing challenges are documented somewhere beyond the README itself. MDX also makes the challenge files readable as plain text in any Markdown viewer, which means contributors inspecting problems do not need to run the web app. The format trades the convenience of automated grading for simplicity of authorship and browsability. ## Accessing the Collection Without a Local Setup The README directs all readers to jscodechallenges.vercel.app rather than to any local setup steps. No clone, install, or build instructions appear in the README. This design means the project expects to be consumed as a website rather than as a library or command-line tool. For a developer preparing for an interview on short notice, this is practical. There is nothing to configure, no package manager to run, and no Node version to align. Opening a browser and navigating to the site is the entire entry point. Vercel deploys automatically when the main branch updates, so the website reflects the current state of the repository. A visitor does not need to track repository pushes manually. For anyone who wants a local copy, the web/ directory is the right starting point. The repository does not document how to install and start that application, so a local setup requires reading the contents of web/ to understand its dependencies and start commands. That investigation is outside the README's scope and is not guaranteed to be straightforward without consulting the web framework's own documentation. ## What the Repository Does Not Document The README does not list the total number of challenges, group them by topic, or label them by difficulty. There is no map from challenge to JavaScript concept area, such as closures, promises, or DOM APIs. There is no documented format for solutions or any statement about whether solutions are included alongside problems. A developer deciding whether this collection covers a specific preparation gap cannot answer that from the README alone. Assessing coverage requires visiting the website directly. This is a real limitation for anyone whose preparation time is short and who needs to confirm that a specific area is covered before investing time in the collection. The contributing.md guide addresses adding new challenges, but it cannot fill the gap of a missing index or topic taxonomy in the published README. The website may present challenges in a structured way, but the repository itself carries no documented structure that a reader can audit before visiting the site. The repository also has no GitHub releases. The collection evolves with the main branch. There is no versioned snapshot for someone who wants a stable reference point. ## How It Compares to a Structured Platform Like freeCodeCamp freeCodeCamp is a structured online curriculum with automated grading. A learner progresses through lessons in a defined order, receives immediate feedback on submitted code, and earns certifications on completion. That model suits people who need guided progression through unfamiliar material and who benefit from automated correctness feedback. JavaScript Code Challenges takes a different approach. It is a browsable collection rather than a curriculum. There is no defined order, no automatic grader, no certification path, and no persistent user state. The collection suits a developer who already understands JavaScript well enough to judge their own solutions and wants a bank of interview-style problems to review or to present to candidates. LeetCode, another point of comparison, provides automated grading, difficulty tags, and company-specific problem sets, but it focuses on algorithmic problems rather than language-specific JavaScript patterns like closures or prototype chains. JavaScript Code Challenges emphasizes JavaScript language semantics over abstract data structure problems, which is a different preparation target. The two categories, structured platforms and curated collections, serve different needs. A candidate starting from scratch benefits more from a structured platform. A developer two weeks before an interview who already knows JavaScript benefits from a focused collection of real interview problems, which is the explicit claim of this repository. ## Contributing, License, and Repository Maintenance The repository includes three files that define its community norms. The contributing.md file documents the process for suggesting or improving challenges. The CODE_OF_CONDUCT.md sets expectations for contributor behavior. Both files sit at the repository root alongside the README. The project is released under the MIT license. MIT permits unrestricted use, modification, and redistribution, including in commercial or internal interview tooling. The only requirement is that the license notice is preserved in copies. The last push to the repository was on 2026-04-01. No GitHub releases have been created; the main branch always represents the current version of the collection. The homepage at jscodechallenges.vercel.app stays in sync with that branch automatically through Vercel's deployment integration. For interviewers who want to fork the repository and customize the challenge set for their team, the MIT license and MDX format together make that straightforward. Each challenge lives in its own MDX file, so adding, removing, or editing problems does not require modifying any application logic in the web/ directory. ## Conclusion Developers looking for a quick, zero-setup bank of modern JavaScript interview problems will find the hosted website practical. Interviewers building a question list and candidates reviewing ES6 and beyond have a stated place in the intended audience. Anyone who needs coverage mapped to specific topics, graded solutions, or a documented difficulty progression should verify those things exist at jscodechallenges.vercel.app before committing to this collection, since the repository README documents none of them. The MIT license permits reuse in commercial or internal interview tooling without restriction. ## FAQ ### How do I access JavaScript Code Challenges? All challenges are available at jscodechallenges.vercel.app without any local installation. The site stays in sync with the main branch of the repository and updates automatically when new challenges are pushed. ### Can I contribute a question to JavaScript Code Challenges? The repository includes a contributing.md file that documents the process for adding or improving challenges. A CODE_OF_CONDUCT.md is also present, setting expectations for contributor interactions. ### What license does JavaScript Code Challenges use? JavaScript Code Challenges is released under the MIT license, which permits unrestricted use, modification, and redistribution. The LICENSE file is in the repository root. ## Sources - [Issues](https://github.com/sadanandpai/javascript-code-challenges/issues) - [License: MIT](https://github.com/sadanandpai/javascript-code-challenges/blob/main/LICENSE) - [Project website](https://jscodechallenges.vercel.app) - [README](https://github.com/sadanandpai/javascript-code-challenges/blob/main/README.md) - [sadanandpai/javascript-code-challenges on GitHub](https://github.com/sadanandpai/javascript-code-challenges) --- Hysen Labs editorial analysis, written from the project's own repository and release notes. Cite the canonical page: https://hysenlabs.com/projects/sadanandpai-javascript-code-challenges