Code Platforms
A catalog of places to learn, practice, and build code — DSA interview prep, competitive programming, cloud IDEs, MOOCs, and portfolios. You can navigate, find Hub (all catalogs), and browse Sister repos.
Disclaimer: Features and pricing change. Use official sites only. See resources/stay-safe.md for fake “coding job” scams.
Pages: student-dev-catalogs · oss-programs-and-hackathons · build-grants · hack-safe · ai-catalog · coding-platforms · public-apis · design-for-devs · cloud-student · maker-student · game-dev-student · never-your-sounds
Interview prep & DSA
| Platform | Best for | Official |
|---|---|---|
| LeetCode | FAANG-style DSA | leetcode.com |
| HackerRank | Skills certs + DSA | hackerrank.com |
| NeetCode | Curated LeetCode paths | neetcode.io |
| AlgoExpert | Paid structured DSA | algoexpert.io |
| GeeksforGeeks | DSA + articles (India-heavy) | geeksforgeeks.org |
| InterviewBit | Structured tracks | interviewbit.com |
| Pramp | Peer mock interviews | pramp.com |
| Exponent | PM / eng interview prep | tryexponent.com |
Competitive programming
| Platform | Best for | Official |
|---|---|---|
| Codeforces | Global CP contests | codeforces.com |
| AtCoder | Japanese/global CP | atcoder.jp |
| CodeChef | Long contests, India | codechef.com |
| CSES Problem Set | Finnish curated set | cses.fi |
| USACO Guide | USACO training | usaco.guide |
| ICPC | Collegiate team contests | icpc.global |
| Kaggle (code comps) | ML + notebooks | kaggle.com |
Learn to code (courses & paths)
| Platform | Best for | Official |
|---|---|---|
| freeCodeCamp | Free full-stack path | freecodecamp.org |
| The Odin Project | Web dev OSS curriculum | theodinproject.com |
| CS50 | Harvard intro CS | cs50.harvard.edu |
| MDN Learn | Web fundamentals | developer.mozilla.org |
| Scrimba | Interactive front-end | scrimba.com |
| Codecademy | Guided courses | codecademy.com |
| Khan Academy | CS basics | khanacademy.org/computing |
| Boot.dev | Backend/Go gamified | boot.dev |
| Exercism | Mentored practice tracks | exercism.org |
| Rustlings | Learn Rust CLI | github.com/rust-lang/rustlings |
Cloud IDEs & notebooks
| Platform | Best for | Official |
|---|---|---|
| GitHub Codespaces | Cloud dev env | github.com/features/codespaces |
| Gitpod | Cloud dev env | gitpod.io |
| Replit | Browser IDE + deploy | replit.com |
| CodeSandbox | Front-end sandboxes | codesandbox.io |
| StackBlitz | WebContainer projects | stackblitz.com |
| Google Colab | Python / ML notebooks | colab.research.google.com |
| Jupyter | Local/cloud notebooks | jupyter.org |
| Deepnote | Collaborative notebooks | deepnote.com |
Git, portfolio & deploy
| Platform | Best for | Official |
|---|---|---|
| GitHub | Repos + Actions | github.com |
| GitLab | Repos + CI | gitlab.com |
| Vercel | Front-end deploy | vercel.com |
| Netlify | Static / JAMstack | netlify.com |
| Render | Full-stack hosting | render.com |
| Railway | App hosting | railway.app |
MOOCs & degrees (online)
| Platform | Best for | Official |
|---|---|---|
| Coursera | University courses | coursera.org |
| edX | University courses | edx.org |
| MIT OpenCourseWare | Free MIT materials | ocw.mit.edu |
| Class Central | MOOC aggregator | classcentral.com |
India-focused
| Platform | Best for | Official |
|---|---|---|
| Unstop | Competitions + hiring | unstop.com |
| CodeChef | CP + learning | codechef.com |
| GeeksforGeeks | DSA + prep | geeksforgeeks.org |
| PrepInsta | Aptitude + company prep | prepinsta.com |
| Coding Ninjas / similar | Paid bootcamps — verify official domain | Search official site before pay |
Open source contribution (next step after practice)
| Resource | Official |
|---|---|
| OSS programs & hackathons guide | oss-programs-and-hackathons |
| First PR playbook | first-contribution.md |
Contribute
CONTRIBUTING.md — official links only.