90 GitHub Repositories Every Developer Must Know

Want to level up your coding, stay updated with new tech, and join the world’s best developer community? Explore these 90 must-know GitHub repositories! From learning resources and code snippets to open-source tools and real-world projects, these repos will help you master programming, ace interviews, and contribute to global innovation no matter your experience level.

I’m Riten, founder of Fueler a platform that helps freelancers and professionals get hired through their work samples. In this article, I’ll share 90 essential GitHub repositories every developer should know in 2025. But remember, it’s not just about browsing code. Presenting your own projects in a smart portfolio is the real shortcut to trust and credibility in tech. Your GitHub and portfolio together are your proof of skill.

1. freeCodeCamp/freeCodeCamp

freeCodeCamp offers a full, interactive curriculum for learning web development, JavaScript, and computer science. You can work through thousands of coding challenges, build real projects, and earn certifications. The repo also has a huge, supportive community. It’s perfect for beginners and experienced developers who want to learn by doing and build a strong portfolio.

2. TheAlgorithms/Python

This repository contains hundreds of algorithms implemented in Python, covering everything from basic sorting to advanced data structures. Each algorithm is well-documented and easy to follow. It’s an excellent resource for students, interview prep, and anyone wanting to understand how algorithms work in real code. Perfect for hands-on learning and improving your Python skills.

3. EbookFoundation/free-programming-books

This legendary repo compiles thousands of free programming books, tutorials, and online courses in many languages and subjects. Whether you want to learn a new language, dive into data science, or explore web development, you’ll find resources here. It’s a must-have bookmark for developers who love self-learning and want to keep up with new technologies.

4. public-apis/public-apis

public-apis is a massive, categorized list of free APIs for development, including data, finance, games, and more. It’s perfect for finding APIs to use in projects, learning how to integrate external services, or practicing with real-world data. Each entry includes documentation links, making it easy to experiment and expand your coding skills.

5. developer-roadmap/developer-roadmap

This repository features visual roadmaps for frontend, backend, DevOps, and more, showing the skills and tools you should learn for each path. The guides are regularly updated and easy to follow. It’s ideal for planning your learning journey, staying on track with industry trends, and understanding what employers look for in developers.

6. kamranahmedse/roadmap.sh

roadmap.sh offers interactive, up-to-date roadmaps for becoming a software engineer, DevOps specialist, or cloud expert. Each roadmap is visual and breaks down complex skills into manageable steps. It’s great for anyone planning a career in tech, helping you choose the right technologies and focus your learning for maximum impact.

7. danistefanovic/build-your-own-x

This creative repository gathers tutorials and resources for building your own programming language, operating system, database, and more. It’s for curious developers who want to understand how things work under the hood. Working through these projects deepens your technical knowledge and gives you the confidence to tackle complex coding challenges.

8. ossu/computer-science

The Open Source Society University (OSSU) repo offers a complete, self-taught computer science curriculum based on top university courses. It includes video lectures, assignments, and hands-on projects. It’s perfect for anyone who wants a structured, high-quality CS education without the cost of college, and for those preparing for tech interviews.

9. CyC2018/CS-Notes

CS-Notes is a comprehensive collection of computer science notes in both Chinese and English. It covers algorithms, data structures, system design, and common interview questions. The notes are well-organized and concise, making it easy to review key concepts before interviews, exams, or when you just want to refresh your knowledge.

10. trekhleb/javascript-algorithms

This repository offers a rich set of algorithms and data structures implemented in JavaScript, each with clear explanations and code examples. It’s a fantastic resource for frontend and full-stack developers who want to master JavaScript and prepare for technical interviews. It’s also useful for learning best practices and improving your coding efficiency.

11. airbnb/javascript

Airbnb’s JavaScript Style Guide is the industry standard for writing clean, consistent, and maintainable JavaScript code. It provides rules, best practices, and examples for everything from variable naming to function structure. Following this guide helps you write code that is easy to read, debug, and share with other developers in any project or team.

12. 30-seconds/30-seconds-of-code

This repository offers hundreds of short, useful JavaScript code snippets that solve common problems in 30 seconds or less. Each snippet is practical and easy to understand, making it perfect for learning new tricks, speeding up your workflow, and finding quick solutions to everyday coding challenges. Great for both beginners and experienced developers.

13. getify/You-Dont-Know-JS

“You Don’t Know JS” is a deep dive into JavaScript’s core concepts, quirks, and advanced features. The book series is available here for free, with each chapter exploring topics like closures, scope, and async programming. It’s essential reading for anyone who wants to truly master JavaScript and write better, more reliable code.

14. jwasham/coding-interview-university

This repo is a complete study plan for software engineering interviews, covering algorithms, system design, databases, and more. It organizes resources, study links, and tips into a clear roadmap. It’s widely used by job seekers aiming for top tech companies and is perfect for anyone preparing for technical interviews and coding assessments.

15. donnemartin/system-design-primer

The System Design Primer helps you learn how to design large-scale systems, a key skill for senior developer and architect roles. It includes real-world examples, interview questions, and design patterns. The explanations are clear and practical, making it a must-have resource for system design interviews and building scalable applications.

16. LeetCode-OpenSource/vscode-leetcode

This Visual Studio Code extension allows you to solve LeetCode problems directly in your editor. It streamlines coding interview preparation by letting you practice algorithms and data structures efficiently. You can track your progress, test solutions, and stay focused without switching between browser tabs and your coding environment.

17. TheAlgorithms/Java

A comprehensive collection of algorithms and data structures implemented in Java. Each algorithm is well-documented and easy to follow, making it a valuable resource for Java learners, students, and anyone preparing for coding interviews. It’s perfect for hands-on practice and understanding how classic algorithms work in Java.

18. TheAlgorithms/C-Plus-Plus

This repository offers hundreds of algorithms and data structures in C++. It’s ideal for students, competitive programmers, and anyone looking to improve their C++ coding skills. Each algorithm is clearly explained, making it easy to learn and use in your own projects or interview prep.

19. TheAlgorithms/JavaScript

A library of classic algorithms and data structures implemented in JavaScript. Each solution is clear and easy to understand, making it great for web developers and anyone preparing for technical interviews. It’s a practical resource for mastering algorithms in the language of the web.

20. TheAlgorithms/Go

A growing collection of algorithms and data structures written in Go. This repo is useful for Go developers who want to master the language, prepare for interviews, or understand how to implement common algorithms and data structures in a modern, efficient way.

21. TheAlgorithms/Rust

A set of algorithms and data structures implemented in Rust. It’s ideal for developers learning Rust or preparing for systems programming interviews. The repository covers a wide range of topics and is great for understanding how to write safe, efficient code in Rust.

22. TheAlgorithms/PHP

A repository of algorithms and data structures in PHP, covering sorting, searching, and more. It’s a handy reference for PHP developers and those interested in backend development. The code is well-organized and easy to adapt for real-world projects or interview preparation.

23. TheAlgorithms/Swift

A collection of algorithms and data structures for Swift developers. This repo helps you learn Swift fundamentals, prepare for iOS development interviews, and understand how classic algorithms work in Apple’s programming language. Each example is clear and easy to follow.

24. TheAlgorithms/Kotlin

Algorithms and data structures in Kotlin, suitable for Android and backend developers. This repository is a practical resource for learning Kotlin through real code, and it’s perfect for interview prep or enhancing your understanding of the language.

25. TheAlgorithms/TypeScript

A library of algorithms and data structures in TypeScript, perfect for web and full-stack developers working with modern JavaScript frameworks. Each algorithm is well-documented, making it easy to learn and use in real projects.

26. TheAlgorithms/Scala

A set of classic algorithms and data structures implemented in Scala. It’s useful for functional programming enthusiasts and Scala learners who want to deepen their understanding of algorithms in a modern, expressive language.

27. TheAlgorithms/Ruby

A collection of algorithms and data structures in Ruby. This repo is great for Rubyists and those preparing for coding interviews. Each algorithm is well-explained and easy to use in your own projects or for learning purposes.

28. TheAlgorithms/Julia

A repository of algorithms and data structures in Julia, ideal for scientific computing and data analysis. The code is clear and practical, making it a good resource for developers working in research, analytics, or high-performance computing.

29. TheAlgorithms/C

A comprehensive set of algorithms and data structures in C. It’s essential for low-level programming, embedded systems, and interview prep. The code is well-documented and covers a wide range of topics, making it a valuable reference for C learners.

30. TheAlgorithms/Haskell

A library of algorithms and data structures in Haskell. It’s perfect for functional programming learners and those interested in advanced coding techniques. Each example is clear and demonstrates the power of functional programming in solving classic problems.

31. TheAlgorithms/Perl

A collection of algorithms and data structures in Perl, useful for scripting and automation tasks. The code is easy to understand and adapt, making it a practical resource for Perl developers and those interested in automating everyday tasks.

32. TheAlgorithms/Shell

Classic algorithms and data structures implemented in shell scripts. This repo is great for DevOps, automation, and system administration tasks. It helps you understand how to solve problems using shell scripting and command-line tools.

33. TheAlgorithms/Dart

A set of algorithms and data structures in Dart, useful for Flutter and mobile app developers. The repository covers a range of topics and is perfect for learning how to implement classic algorithms in Dart.

34. TheAlgorithms/Elixir

A library of algorithms and data structures in Elixir, perfect for backend and distributed systems developers. The code is clear and practical, making it a good resource for learning Elixir through real examples.

35. TheAlgorithms/Matlab-Octave

Algorithms and data structures for Matlab and Octave users, ideal for engineering and scientific computing. The code is well-organized and easy to use for simulations, analysis, and academic projects.

36. TheAlgorithms/R

A repository of algorithms and data structures in R, great for data science and statistical computing. Each example is clear and practical, making it a valuable resource for R learners and analysts.

37. TheAlgorithms/COBOL

Classic algorithms and data structures in COBOL, useful for legacy systems and financial applications. The repository is a helpful reference for developers working with older technologies or maintaining enterprise systems.

38. TheAlgorithms/Fortran

A set of algorithms and data structures in Fortran, ideal for scientific and engineering projects. The code is clear and practical, making it a good resource for learning Fortran or working in research environments.

39. TheAlgorithms/PL-SQL

A library of algorithms and data structures in PL/SQL, useful for database developers and SQL learners. The code is well-documented and covers a range of database operations and logic.

40. TheAlgorithms/Assembly

Algorithms and data structures in Assembly language, perfect for learning low-level programming and computer architecture. The code is clear and practical, making it a valuable resource for understanding how computers work at the hardware level.

41. TheAlgorithms/Prolog

A collection of algorithms and data structures in Prolog, great for logic programming and AI research. The repository covers a range of topics and is perfect for learning how to solve problems using declarative programming.

42. TheAlgorithms/Objective-C

A repository of algorithms and data structures in Objective-C, useful for iOS and macOS developers. The code is well-organized and easy to use for learning or interview prep.

43. TheAlgorithms/VisualBasic

Algorithms and data structures in Visual Basic, great for legacy software maintenance and automation. The repository is a practical resource for developers working with older Microsoft technologies.

44. TheAlgorithms/OCaml

A set of algorithms and data structures in OCaml, ideal for functional programming and academic projects. The code is clear and practical, making it a good resource for learning OCaml.

45. TheAlgorithms/Erlang

A library of algorithms and data structures in Erlang, useful for distributed systems and telecom applications. The code is well-documented and covers a range of topics relevant to real-world systems.

46. TheAlgorithms/Groovy

Algorithms and data structures in Groovy, suitable for scripting and automation tasks. The repository is practical for developers who want to learn Groovy or automate routine coding tasks.

47. TheAlgorithms/Lua

A collection of algorithms and data structures in Lua, perfect for game development and embedded systems. The code is clear and easy to adapt for your own projects.

48. TheAlgorithms/Scheme

A set of algorithms and data structures in Scheme, useful for learning Lisp and functional programming. The code is practical and demonstrates the power of Scheme for solving classic problems.

49. TheAlgorithms/F#

A library of algorithms and data structures in F#, ideal for .NET and functional programming developers. The code is well-organized and easy to use for learning or interview preparation.

50. TheAlgorithms/Clojure

Algorithms and data structures in Clojure, perfect for JVM and functional programming enthusiasts. The repository covers a range of topics and is great for learning how to use Clojure in real projects.

51. TheAlgorithms/Crystal

A collection of algorithms and data structures in Crystal, suitable for high-performance applications. The code is clear and practical, making it a good resource for learning Crystal.

52. TheAlgorithms/Smalltalk

A set of algorithms and data structures in Smalltalk, great for object-oriented programming learners. The code is well-organized and easy to use for learning or academic projects.

53. TheAlgorithms/Delphi

Algorithms and data structures in Delphi, suitable for desktop and enterprise software development. The repository is a practical resource for developers working with Delphi.

54. TheAlgorithms/Pascal

A library of algorithms and data structures in Pascal, useful for academic projects and legacy systems. The code is clear and easy to adapt for your own use.

55. TheAlgorithms/Basic

Algorithms and data structures in Basic, perfect for beginners and educational purposes. The repository is a good starting point for new programmers.

56. awesome-selfhosted/awesome-selfhosted

This repository lists hundreds of self-hosted software solutions for everything from web servers to project management. Each entry is open source and can be run on your own servers. It’s a valuable resource for developers who want to control their data and learn about deploying real-world applications.

57. sindresorhus/awesome

The “awesome” repo is a giant curated list of the best resources, tools, and libraries for almost every programming language and topic. It’s constantly updated and community-driven. Bookmark this for discovering new frameworks, tutorials, and open-source projects in any area of tech.

58. vinta/awesome-python

A curated list of awesome Python frameworks, libraries, and software. From web development to data science, this repo helps you discover the best tools for any Python project. It’s perfect for finding new packages, learning best practices, and staying up to date with the Python community.

59. enaqx/awesome-react

A comprehensive list of React resources, libraries, and tools. Whether you’re building web apps or mobile apps with React Native, this repo helps you find the best UI components, tutorials, and boilerplates. It’s essential for React developers who want to work efficiently and learn from the community.

60. sindresorhus/awesome-nodejs

A curated list of Node.js frameworks, libraries, and tools. This repo covers everything from web servers to testing frameworks, helping you build scalable backend applications. It’s a must-have resource for Node.js developers who want to stay current and discover new ways to improve their workflow.

61. awesome-go/awesome-go

A curated list of Go frameworks, libraries, and software. This repo helps you find the best tools for web development, networking, and more in the Go ecosystem. It’s perfect for Go developers looking to expand their toolkit and learn best practices.

62. akullpp/awesome-java

A comprehensive list of Java frameworks, libraries, and tools. This repo covers everything from web development to machine learning, helping you find the right resources for any Java project. It’s a valuable reference for Java developers at any level.

63. awesome-php/awesome-php

A curated list of PHP libraries, frameworks, and tools. This repo helps you discover the best resources for web development, automation, and more. It’s perfect for PHP developers who want to stay updated and build better applications.

64. awesome-ruby/awesome-ruby

A comprehensive list of Ruby frameworks, libraries, and tools. This repo covers web development, testing, and more, helping you find the best resources for any Ruby project. It’s essential for Rubyists who want to learn from the community and improve their workflow.

65. awesome-cpp/awesome-cpp

A curated list of C++ frameworks, libraries, and tools. This repo helps you discover the best resources for system programming, game development, and more. It’s a valuable reference for C++ developers who want to stay current and learn best practices.

66. awesome-dotnet/awesome-dotnet

A comprehensive list of .NET libraries, frameworks, and tools. This repo covers web development, desktop apps, and more, helping you find the best resources for any .NET project. It’s perfect for .NET developers who want to expand their knowledge and toolkit.

67. awesome-vue/awesome-vue

A curated list of Vue.js resources, libraries, and tools. This repo helps you find the best UI components, tutorials, and boilerplates for building modern web apps. It’s essential for Vue developers who want to work efficiently and learn from the community.

68. awesome-angular/awesome-angular

A comprehensive list of Angular resources, libraries, and tools. This repo covers everything from UI components to testing frameworks, helping you build scalable web applications. It’s a valuable resource for Angular developers at any level.

69. awesome-react-native/awesome-react-native

A curated list of React Native resources, libraries, and tools. This repo helps you find the best packages for building cross-platform mobile apps. It’s perfect for React Native developers who want to stay updated and learn from the community.

70. awesome-electron/awesome-electron

A comprehensive list of Electron resources, libraries, and tools. This repo helps you build cross-platform desktop apps using web technologies. It’s essential for developers who want to create desktop software with JavaScript, HTML, and CSS.

71. awesome-flutter/awesome-flutter

A curated list of Flutter resources, libraries, and tools. This repo helps you find the best packages for building beautiful mobile apps. It’s perfect for Flutter developers who want to work efficiently and stay up to date with the ecosystem.

72. awesome-django/awesome-django

A comprehensive list of Django resources, libraries, and tools. This repo covers everything from web development to testing, helping you build scalable web applications with Python. It’s a valuable resource for Django developers at any level.

73. awesome-spring-boot/awesome-spring-boot

A curated list of Spring Boot resources, libraries, and tools. This repo helps you build modern, scalable Java applications. It’s perfect for Java developers working with Spring Boot who want to learn best practices and discover new tools.

74. awesome-machine-learning/awesome-machine-learning

A comprehensive list of machine learning frameworks, libraries, and tools. This repo covers Python, Java, C++, and more, helping you find the best resources for any ML project. It’s essential for anyone interested in AI and data science.

75. tensorflow/tensorflow

TensorFlow is Google’s open-source library for machine learning and deep learning. The repo includes code, documentation, and tutorials for building neural networks and AI models. It’s widely used in industry and research, making it a must-know for anyone interested in artificial intelligence.

76. scikit-learn/scikit-learn

scikit-learn is a powerful Python library for machine learning, offering simple and efficient tools for data mining and analysis. The repo includes code, examples, and documentation for everything from regression to clustering. It’s perfect for beginners and professionals working in data science.

77. keras-team/keras

Keras is a high-level neural networks API written in Python, running on top of TensorFlow. The repo provides code, tutorials, and guides for building deep learning models. It’s user-friendly and ideal for rapid prototyping and experimentation in AI projects.

78. pytorch/pytorch

PyTorch is an open-source machine learning library developed by Facebook. The repo includes code, documentation, and examples for building neural networks and AI models. It’s popular in research and industry, making it a must-know for anyone working in deep learning.

79. huggingface/transformers

This repository provides state-of-the-art natural language processing tools and pre-trained models. It’s widely used for building chatbots, language translators, and AI assistants. The code and documentation make it easy to experiment with cutting-edge NLP technology.

80. openai/gym

OpenAI Gym is a toolkit for developing and comparing reinforcement learning algorithms. The repo provides environments, examples, and documentation for training AI agents. It’s perfect for anyone interested in machine learning, robotics, or artificial intelligence research.

81. openai/whisper

Whisper is an automatic speech recognition system by OpenAI. The repo provides code, models, and examples for transcribing audio to text. It’s a valuable resource for developers working on voice assistants, transcription services, or accessibility tools.

82. openai/openai-cookbook

This repository contains practical guides, code snippets, and best practices for using OpenAI’s APIs and models. It’s perfect for developers building AI-powered applications, chatbots, or integrating GPT models into their projects.

83. microsoft/vscode

Visual Studio Code is a popular open-source code editor from Microsoft. The repo includes the editor’s source code, extensions, and documentation. Developers can contribute to the project or learn how to build their own extensions for a customizable coding environment.

84. facebook/react

React is a widely used JavaScript library for building user interfaces. The repo provides source code, documentation, and examples for creating fast, interactive web apps. It’s essential for frontend and full-stack developers.

85. vercel/next.js

Next.js is a powerful React framework for building server-rendered and static web applications. The repo includes code, documentation, and examples for creating fast, scalable websites. It’s perfect for developers who want to build modern web apps with React.

86. nuxt/nuxt.js

Nuxt.js is a framework for building server-rendered Vue.js applications. The repo provides code, documentation, and examples for creating SEO-friendly, performant web apps. It’s ideal for Vue developers who want to build modern websites.

87. expressjs/express

Express is a minimal and flexible Node.js web application framework. The repo includes code, documentation, and examples for building APIs and web servers. It’s a must-know for backend and full-stack developers working with Node.js.

88. nestjs/nest

NestJS is a progressive Node.js framework for building efficient, scalable server-side applications. The repo provides code, documentation, and examples for creating enterprise-grade APIs. It’s perfect for developers who want to use TypeScript and modern architecture patterns.

89. fastify/fastify

Fastify is a fast and low-overhead web framework for Node.js. The repo includes code, documentation, and plugins for building high-performance APIs. It’s ideal for developers who need speed and scalability in their backend projects.

90. electron/electron

Electron allows you to build cross-platform desktop apps using JavaScript, HTML, and CSS. The repo provides code, documentation, and examples for creating desktop software. It’s perfect for web developers who want to expand into desktop application development.

Final Thought

Exploring and contributing to these 90 essential GitHub repositories can truly transform your journey as a developer. They offer not just code, but also learning, inspiration, and community. Stay curious, keep building, and remember—your growth accelerates when you learn from others and share your own work. Combine these resources with a strong portfolio to stand out in today’s tech world.

FAQs

1. Why should every developer follow these GitHub repositories?

They provide up-to-date code samples, best practices, and learning resources that help you improve your skills, solve real problems, and stay relevant in the fast-changing tech industry.

2. How can I contribute to open-source repositories as a beginner?

Start by reading the contribution guidelines, look for beginner-friendly issues, fork the repository, make your changes, and submit a pull request. Engaging with the community and asking questions also helps you learn faster.

3. Which repositories are most helpful for coding interviews?

Repositories like Coding Interview University, The Algorithms, and The System Design Primer offer structured interview prep, coding questions, and detailed solutions to help you succeed in technical interviews.

4. Are there GitHub repositories for learning new programming languages?

Yes, repos like freeCodeCamp, Free Programming Books, and Project-Based Learning offer tutorials, hands-on projects, and resources for learning almost any programming language from scratch.

5. How can I showcase my GitHub work to potential employers?

Highlight your best repositories in your portfolio, write clear READMEs, and document your contributions. Platforms like Fueler help you organize and present your GitHub work to attract remote jobs and freelance opportunities.

What is Fueler Portfolio?

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You can create your portfolio on Fueler, thousands of freelancers around the world use Fueler to create their professional-looking portfolios and become financially independent. Discover inspiration for your portfolio

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