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## Build Your Own Technology

This repository is a compilation of well-written, step-by-step guides for re-creating our favorite technologies from scratch. 🚀

> *What I cannot create, I do not understand — Richard Feynman.*

It's a great way to learn.

* [3D Renderer](#build-your-own-3d-renderer)
* [Augmented Reality](#build-your-own-augmented-reality)
* [BitTorrent Client](#build-your-own-bittorrent-client)
* [Blockchain / Cryptocurrency](#build-your-own-blockchain--cryptocurrency)
* [Bot](#build-your-own-bot)
* [Command-Line Tool](#build-your-own-command-line-tool)
* [Database](#build-your-own-database)
* [Docker](#build-your-own-docker)
* [Emulator / Virtual Machine](#build-your-own-emulator--virtual-machine)
* [Front-end Framework / Library](#build-your-own-front-end-framework--library)
* [Game](#build-your-own-game)
* [Git](#build-your-own-git)
* [Network Stack](#build-your-own-network-stack)
* [Neural Network](#build-your-own-neural-network)
* [Operating System](#build-your-own-operating-system)
* [Physics Engine](#build-your-own-physics-engine)
* [Programming Language](#build-your-own-programming-language)
* [Regex Engine](#build-your-own-regex-engine)
* [Search Engine](#build-your-own-search-engine)
* [Shell](#build-your-own-shell)
* [Template Engine](#build-your-own-template-engine)
* [Text Editor](#build-your-own-text-editor)
* [Visual Recognition System](#build-your-own-visual-recognition-system)
* [Voxel Engine](#build-your-own-voxel-engine)
* [Web Browser](#build-your-own-web-browser)
* [Web Server](#build-your-own-web-server)
* [Uncategorized](#uncategorized) ---

## Tutorials

#### Build your own `3D Renderer`

* [**C++**: _Introduction to Ray Tracing: a Simple Method for Creating 3D Images_](https://www.scratchapixel.com/lessons/3d-basic-rendering/introduction-to-ray-tracing/how-does-it-work)
* [**C++**: _How OpenGL works: software rendering in 500 lines of code_](https://github.com/ssloy/tinyrenderer/wiki)
* [**C++**: _Raycasting engine of Wolfenstein 3D_](http://lodev.org/cgtutor/raycasting.html)
* [**C++**: _Physically Based Rendering:From Theory To Implementation_](http://www.pbr-book.org/)
* [**C++**: _Ray Tracing in One Weekend_](https://raytracing.github.io/books/RayTracingInOneWeekend.html)
* [**C++**: _Rasterization: a Practical Implementation_](https://www.scratchapixel.com/lessons/3d-basic-rendering/rasterization-practical-implementation/overview-rasterization-algorithm)
* [**C# / TypeScript / JavaScript**: _Learning how to write a 3D soft engine from scratch in C#, TypeScript or JavaScript_](https://www.davrous.com/2013/06/13/tutorial-series-learning-how-to-write-a-3d-soft-engine-from-scratch-in-c-typescript-or-javascript/)
* [**Java / JavaScript**: _Build your own 3D renderer_](https://avik-das.github.io/build-your-own-raytracer/)
* [**Java**: _How to create your own simple 3D render engine in pure Java_](http://blog.rogach.org/2015/08/how-to-create-your-own-simple-3d-render.html)
* [**JavaScript / Pseudocode**: _Computer Graphics from scratch_](http://www.gabrielgambetta.com/computer-graphics-from-scratch/introduction.html)
* [**Python**: _A 3D Modeller_](http://aosabook.org/en/500L/a-3d-modeller.html)

---

#### Build your own `Augmented Reality`

* [**C#**: _How To: Augmented Reality App Tutorial for Beginners with Vuforia and Unity 3D_](https://www.youtube.com/watch?v=uXNjNcqW4kY) [video]
* [**C#**: _How To Unity ARCore_](https://www.youtube.com/playlist?list=PLKIKuXdn4ZMjuUAtdQfK1vwTZPQn_rgSv) [video]
* [**C#**: _AR Portal Tutorial with Unity_](https://www.youtube.com/playlist?list=PLPCqNOwwN794Gz5fzUSi1p4OqLU0HTmvn) [video]
* [**C#**: _How to create a Dragon in Augmented Reality in Unity ARCore_](https://www.youtube.com/watch?v=qTSDPkPyPqs) [video]
* [**C#**: _How to Augmented Reality AR Tutorial: ARKit Portal to the Upside Down_](https://www.youtube.com/watch?v=Z5AmqMuNi08) [video]
* [**Python**: _Augmented Reality with Python and OpenCV_](https://bitesofcode.wordpress.com/2017/09/12/augmented-reality-with-python-and-opencv-part-1/)

---

#### Build your own `BitTorrent Client`

* [**C#**: _Building a BitTorrent client from scratch in C#_](https://www.seanjoflynn.com/research/bittorrent.html)
* [**Go**: _Building a BitTorrent client from the ground up in Go_](https://blog.jse.li/posts/torrent/)
* [**Nim**: _Writing a Bencode Parser_](https://xmonader.github.io/nimdays/day02_bencode.html)
* [**Node.js**: _Write your own bittorrent client_](https://allenkim67.github.io/programming/2016/05/04/how-to-make-your-own-bittorrent-client.html)
* [**Python**: _A BitTorrent client in Python 3.5_](http://markuseliasson.se/article/bittorrent-in-python/)

---

#### Build your own `Blockchain / Cryptocurrency`

* [**ATS**: _Functional Blockchain_](https://beta.observablehq.com/@galletti94/functional-blockchain)
* [**C#**: _Programming The Blockchain in C#_](https://programmingblockchain.gitbooks.io/programmingblockchain/)
* [**Crystal**: _Write your own blockchain and PoW algorithm using Crystal_](https://medium.com/@bradford_hamilton/write-your-own-blockchain-and-pow-algorithm-using-crystal-d53d5d9d0c52)
* [**Go**: _Building Blockchain in Go_](https://jeiwan.net/posts/building-blockchain-in-go-part-1/)
* [**Go**: _Code your own blockchain in less than 200 lines of Go_](https://medium.com/@mycoralhealth/code-your-own-blockchain-in-less-than-200-lines-of-go-e296282bcffc)
* [**Java**: _Creating Your First Blockchain with Java_](https://medium.com/programmers-blockchain/create-simple-blockchain-java-tutorial-from-scratch-6eeed3cb03fa)
* [**JavaScript**: _A cryptocurrency implementation in less than 1500 lines of code_](https://github.com/conradoqg/naivecoin)
* [**JavaScript**: _Build your own Blockchain in JavaScript_](https://github.com/nambrot/blockchain-in-js)
* [**JavaScript**: _Learn & Build a JavaScript Blockchain_](https://medium.com/digital-alchemy-holdings/learn-build-a-javascript-blockchain-part-1-ca61c285821e)
* [**JavaScript**: _Creating a blockchain with JavaScript_](https://github.com/SavjeeTutorials/SavjeeCoin)
* [**JavaScript**: _How To Launch Your Own Production-Ready Cryptocurrency_](https://hackernoon.com/how-to-launch-your-own-production-ready-cryptocurrency-ab97cb773371)
* [**JavaScript**: _Writing a Blockchain in Node.js_](https://www.smashingmagazine.com/2020/02/cryptocurrency-blockchain-node-js/)
* [**Kotlin**: _Let’s implement a cryptocurrency in Kotlin_](https://medium.com/@vasilyf/lets-implement-a-cryptocurrency-in-kotlin-part-1-blockchain-8704069f8580)
* [**Python**: _Learn Blockchains by Building One_](https://hackernoon.com/learn-blockchains-by-building-one-117428612f46)
* [**Python**: _Build your own blockchain: a Python tutorial_](http://ecomunsing.com/build-your-own-blockchain)
* [**Python**: _A Practical Introduction to Blockchain with Python_](http://adilmoujahid.com/posts/2018/03/intro-blockchain-bitcoin-python/)
* [**Python**: _Let’s Build the Tiniest Blockchain_](https://medium.com/crypto-currently/lets-build-the-tiniest-blockchain-e70965a248b)
* [**Ruby**: _Programming Blockchains Step-by-Step (Manuscripts Book Edition)_](https://github.com/yukimotopress/programming-blockchains-step-by-step)
* [**Scala**: _How to build a simple actor-based blockchain_](https://medium.freecodecamp.org/how-to-build-a-simple-actor-based-blockchain-aac1e996c177)
* [**TypeScript**: _Naivecoin: a tutorial for building a cryptocurrency_](https://lhartikk.github.io/)
* [**TypeScript**: _NaivecoinStake: a tutorial for building a cryptocurrency with the Proof of Stake consensus_](https://naivecoinstake.learn.uno/)
* [**Rust**: _Building A Blockchain in Rust & Substrate_](https://hackernoon.com/building-a-blockchain-in-rust-and-substrate-a-step-by-step-guide-for-developers-kc223ybp)

---

#### Build your own `Bot`

* [**Haskell**: _Roll your own IRC bot_](https://wiki.haskell.org/Roll_your_own_IRC_bot)
* [**Node.js**: _Creating a Simple Facebook Messenger AI Bot with API.ai in Node.js_](https://tutorials.botsfloor.com/creating-a-simple-facebook-messenger-ai-bot-with-api-ai-in-node-js-50ae2fa5c80d)
* [**Node.js**: _How to make a responsive telegram bot_](https://www.sohamkamani.com/blog/2016/09/21/making-a-telegram-bot/)
* [**Node.js**: _Create a Discord bot_](https://discordjs.guide/)
* [**Node.js**: _gifbot - Building a GitHub App_](https://blog.scottlogic.com/2017/05/22/gifbot-github-integration.html)
* [**Node.js**: _Building A Simple AI Chatbot With Web Speech API And Node.js_](https://www.smashingmagazine.com/2017/08/ai-chatbot-web-speech-api-node-js/)
* [**Python**: _How to Build Your First Slack Bot with Python_](https://www.fullstackpython.com/blog/build-first-slack-bot-python.html)
* [**Python**: _How to build a Slack Bot with Python using Slack Events API & Django under 20 minute_](https://medium.com/freehunch/how-to-build-a-slack-bot-with-python-using-slack-events-api-django-under-20-minute-code-included-269c3a9bf64e)
* [**Python**: _Build a Reddit Bot_](http://pythonforengineers.com/build-a-reddit-bot-part-1/)
* [**Python**: _How To Make A Reddit Bot_](https://www.youtube.com/watch?v=krTUf7BpTc0) [video]
* [**Python**: _How To Create a Telegram Bot Using Python_](https://www.freecodecamp.org/news/how-to-create-a-telegram-bot-using-python/)
* [**Python**: _Create a Twitter Bot in Python Using Tweepy_](https://medium.freecodecamp.org/creating-a-twitter-bot-in-python-with-tweepy-ac524157a607)
* [**Python**: _Creating Reddit Bot with Python & PRAW_](https://www.youtube.com/playlist?list=PLIFBTFgFpoJ9vmYYlfxRFV6U_XhG-4fpP) [video]
* [**R**: _Build A Cryptocurrency Trading Bot with R_](https://towardsdatascience.com/build-a-cryptocurrency-trading-bot-with-r-1445c429e1b1)
* [**Rust**: _A bot for Starcraft in Rust, C or any other language_](https://habr.com/en/post/436254/)

---

#### Build your own `Command-Line Tool`

* [**Go**: _Visualize your local git contributions with Go_](https://flaviocopes.com/go-git-contributions/)
* [**Go**: _Build a command line app with Go: lolcat_](https://flaviocopes.com/go-tutorial-lolcat/)
* [**Go**: _Building a cli command with Go: cowsay_](https://flaviocopes.com/go-tutorial-cowsay/)
* [**Go**: _Go CLI tutorial: fortune clone_](https://flaviocopes.com/go-tutorial-fortune/)
* [**Nim**: _Writing a stow alternative to manage dotfiles_](https://xmonader.github.io/nimdays/day06_nistow.html)
* [**Node.js**: _Create a CLI tool in Javascript_](https://citw.dev/tutorial/create-your-own-cli-tool)
* [**Rust**: _Command line apps in Rust_](https://rust-cli.github.io/book/index.html)
* [**Rust**: _Writing a Command Line Tool in Rust_](https://mattgathu.dev/2017/08/29/writing-cli-app-rust.html)
* [**Zig**: _Build Your Own CLI App in Zig from Scratch_](https://rebuild-x.github.io/docs/#/./zig/terminal/cli)

---

#### Build your own `Database`

* [**C**: _Let's Build a Simple Database_](https://cstack.github.io/db_tutorial/)
* [**C++**: _Build Your Own Redis from Scratch_](https://build-your-own.org/redis)
* [**C#**: _Build Your Own Database_](https://www.codeproject.com/Articles/1029838/Build-Your-Own-Database)
* [**Clojure**: _An Archaeology-Inspired Database_](http://aosabook.org/en/500L/an-archaeology-inspired-database.html)
* [**Crystal**: _Why you should build your own NoSQL Database_](https://medium.com/@marceloboeira/why-you-should-build-your-own-nosql-database-9bbba42039f5)
* [**Go**: _Build Your Own Database from Scratch: Persistence, Indexing, Concurrency_](https://build-your-own.org/database/)
* [**Go**: _Build Your Own Redis from Scratch_](https://www.build-redis-from-scratch.dev/)
* [**JavaScript**: _Dagoba: an in-memory graph database_](http://aosabook.org/en/500L/dagoba-an-in-memory-graph-database.html)
* [**Python**: _DBDB: Dog Bed Database_](http://aosabook.org/en/500L/dbdb-dog-bed-database.html)
* [**Python**: _Write your own miniature Redis with Python_](http://charlesleifer.com/blog/building-a-simple-redis-server-with-python/)
* [**Ruby**: _Build your own fast, persistent KV store in Ruby_](https://dineshgowda.com/posts/build-your-own-persistent-kv-store/)
* [**Rust**: _Build your own Redis client and server_](https://tokio.rs/tokio/tutorial/setup)

---

#### Build your own `Docker`

* [**C**: _Linux containers in 500 lines of code_](https://blog.lizzie.io/linux-containers-in-500-loc.html)
* [**Go**: _Build Your Own Container Using Less than 100 Lines of Go_](https://www.infoq.com/articles/build-a-container-golang)
* [**Go**: _Building a container from scratch in Go_](https://www.youtube.com/watch?v=8fi7uSYlOdc) [video]
* [**Python**: _A workshop on Linux containers: Rebuild Docker from Scratch_](https://github.com/Fewbytes/rubber-docker)
* [**Python**: _A proof-of-concept imitation of Docker, written in 100% Python_](https://github.com/tonybaloney/mocker)
* [**Shell**: _Docker implemented in around 100 lines of bash_](https://github.com/p8952/bocker)

---

#### Build your own `Emulator / Virtual Machine`

* [**C**: _Home-grown bytecode interpreters_](https://medium.com/bumble-tech/home-grown-bytecode-interpreters-51e12d59b25c)
* [**C**: _Virtual machine in C_](http://web.archive.org/web/20200121100942/https://blog.felixangell.com/virtual-machine-in-c/)
* [**C**: _Write your Own Virtual Machine_](https://justinmeiners.github.io/lc3-vm/)
* [**C**: _Writing a Game Boy emulator, Cinoop_](https://cturt.github.io/cinoop.html)
* [**C++**: _How to write an emulator (CHIP-8 interpreter)_](http://www.multigesture.net/articles/how-to-write-an-emulator-chip-8-interpreter/)
* [**C++**: _Emulation tutorial (CHIP-8 interpreter)_](http://www.codeslinger.co.uk/pages/projects/chip8.html)
* [**C++**: _Emulation tutorial (GameBoy emulator)_](http://www.codeslinger.co.uk/pages/projects/gameboy.html)
* [**C++**: _Emulation tutorial (Master System emulator)_](http://www.codeslinger.co.uk/pages/projects/mastersystem/memory.html)
* [**C++**: _NES Emulator From Scratch_](https://www.youtube.com/playlist?list=PLrOv9FMX8xJHqMvSGB_9G9nZZ_4IgteYf) [video]
* [**Common Lisp**: _CHIP-8 in Common Lisp_](http://stevelosh.com/blog/2016/12/chip8-cpu/)
* [**JavaScript**: _GameBoy Emulation in JavaScript_](http://imrannazar.com/GameBoy-Emulation-in-JavaScript)
* [**Python**: _Emulation Basics: Write your own Chip 8 Emulator/Interpreter_](http://omokute.blogspot.com.br/2012/06/emulation-basics-write-your-own-chip-8.html)
* [**Rust**: _0dmg: Learning Rust by building a partial Game Boy emulator_](https://jeremybanks.github.io/0dmg/)

---

#### Build your own `Front-end Framework / Library`

* [**JavaScript**: _WTF is JSX (Let's Build a JSX Renderer)_](https://jasonformat.com/wtf-is-jsx/)
* [**JavaScript**: _A DIY guide to build your own React_](https://github.com/hexacta/didact)
* [**JavaScript**: _Building React From Scratch_](https://www.youtube.com/watch?v=_MAD4Oly9yg) [video]
* [**JavaScript**: _Gooact: React in 160 lines of JavaScript_](https://medium.com/@sweetpalma/gooact-react-in-160-lines-of-javascript-44e0742ad60f)
* [**JavaScript**: _Learn how React Reconciler package works by building your own lightweight React DOM_](https://hackernoon.com/learn-you-some-custom-react-renderers-aed7164a4199)
* [**JavaScript**: _Build Yourself a Redux_](https://zapier.com/engineering/how-to-build-redux/)
* [**JavaScript**: _Let’s Write Redux!_](https://www.jamasoftware.com/blog/lets-write-redux/)
* [**JavaScript**: _Redux: Implementing Store from Scratch_](https://egghead.io/lessons/react-redux-implementing-store-from-scratch) [video]
* [**JavaScript**: _Build Your own Simplified AngularJS in 200 Lines of JavaScript_](https://blog.mgechev.com/2015/03/09/build-learn-your-own-light-lightweight-angularjs/)
* [**JavaScript**: _Make Your Own AngularJS_](http://teropa.info/blog/2013/11/03/make-your-own-angular-part-1-scopes-and-digest.html)
* [**JavaScript**: _How to write your own Virtual DOM_](https://medium.com/@deathmood/how-to-write-your-own-virtual-dom-ee74acc13060)
* [**JavaScript**: _Building a frontend framework, from scratch, with components (templating, state, VDOM)_](https://mfrachet.github.io/create-frontend-framework/)
* [**JavaScript**: _Build your own React_](https://pomb.us/build-your-own-react/)
* [**JavaScript**: _Building a Custom React Renderer_](https://youtu.be/CGpMlWVcHok) [video]

---

#### Build your own `Game`

* [**C**: _Handmade Hero_](https://handmadehero.org/)
* [**C**: _How to Program an NES game in C_](https://nesdoug.com/)
* [**C**: _Chess Engine In C_](https://www.youtube.com/playlist?list=PLZ1QII7yudbc-Ky058TEaOstZHVbT-2hg) [video]
* [**C**: _Let's Make: Dangerous Dave_](https://www.youtube.com/playlist?list=PLSkJey49cOgTSj465v2KbLZ7LMn10bCF9) [video]
* [**C**: _Learn Video Game Programming in C_](https://www.youtube.com/playlist?list=PLT6WFYYZE6uLMcPGS3qfpYm7T_gViYMMt) [video]
* [**C**: _Coding A Sudoku Solver in C_](https://www.youtube.com/playlist?list=PLkTXsX7igf8edTYU92nU-f5Ntzuf-RKvW) [video]
* [**C**: _Coding a Rogue/Nethack RPG in C_](https://www.youtube.com/playlist?list=PLkTXsX7igf8erbWGYT4iSAhpnJLJ0Nk5G) [video]
* [**C**: _On Tetris and Reimplementation_](https://brennan.io/2015/06/12/tetris-reimplementation/)
* [**C++**: _Breakout_](https://learnopengl.com/In-Practice/2D-Game/Breakout)
* [**C++**: _Beginning Game Programming v2.0_](http://lazyfoo.net/tutorials/SDL/)
* [**C++**: _Tetris tutorial in C++ platform independent focused in game logic for beginners_](http://javilop.com/gamedev/tetris-tutorial-in-c-platform-independent-focused-in-game-logic-for-beginners/)
* [**C++**: _Remaking Cavestory in C++_](https://www.youtube.com/watch?v=ETvApbD5xRo&list=PLNOBk_id22bw6LXhrGfhVwqQIa-M2MsLa) [video]
* [**C++**: _Reconstructing Cave Story_](https://www.youtube.com/playlist?list=PL006xsVEsbKjSKBmLu1clo85yLrwjY67X) [video]
* [**C++**: _Space Invaders from Scratch_](http://nicktasios.nl/posts/space-invaders-from-scratch-part-1.html)
* [**C#**: _Learn C# by Building a Simple RPG_](http://scottlilly.com/learn-c-by-building-a-simple-rpg-index/)
* [**C#**: _Creating a Roguelike Game in C#_](https://roguesharp.wordpress.com/)
* [**C#**: _Build a C#/WPF RPG_](https://scottlilly.com/build-a-cwpf-rpg/)
* [**Go**: _Games With Go_](https://www.youtube.com/playlist?list=PLDZujg-VgQlZUy1iCqBbe5faZLMkA3g2x) [video]
* [**Java**: _Code a 2D Game Engine using Java - Full Course for Beginners_](https://www.youtube.com/watch?v=025QFeZfeyM) [video]
* [**Java**: _3D Game Development with LWJGL 3_](https://lwjglgamedev.gitbooks.io/3d-game-development-with-lwjgl/content/)
* [**JavaScript**: _2D breakout game using Phaser_](https://developer.mozilla.org/en-US/docs/Games/Tutorials/2D_breakout_game_Phaser)
* [**JavaScript**: _How to Make Flappy Bird in HTML5 With Phaser_](http://www.lessmilk.com/tutorial/flappy-bird-phaser-1)
* [**JavaScript**: _Developing Games with React, Redux, and SVG_](https://auth0.com/blog/developing-games-with-react-redux-and-svg-part-1/)
* [**JavaScript**: _Build your own 8-Ball Pool game from scratch_](https://www.youtube.com/watch?v=aXwCrtAo4Wc) [video]
* [**JavaScript**: _How to Make Your First Roguelike_](https://gamedevelopment.tutsplus.com/tutorials/how-to-make-your-first-roguelike--gamedev-13677)
* [**JavaScript**: _Think like a programmer: How to build Snake using only JavaScript, HTML & CSS_](https://medium.freecodecamp.org/think-like-a-programmer-how-to-build-snake-using-only-javascript-html-and-css-7b1479c3339e)
* [**Lua**: _BYTEPATH_](https://github.com/SSYGEN/blog/issues/30)
* [**Python**: _Developing Games With PyGame_](https://pythonprogramming.net/pygame-python-3-part-1-intro/)
* [**Python**: _Making Games with Python & Pygame_](https://inventwithpython.com/makinggames.pdf) [pdf]
* [**Python**: _Roguelike Tutorial Revised_](http://rogueliketutorials.com/)
* [**Ruby**: _Developing Games With Ruby_](https://leanpub.com/developing-games-with-ruby/read)
* [**Ruby**: _Ruby Snake_](https://www.diatomenterprises.com/gamedev-on-ruby-why-not/)
* [**Rust**: _Adventures in Rust: A Basic 2D Game_](https://a5huynh.github.io/posts/2018/adventures-in-rust/)
* [**Rust**: _Roguelike Tutorial in Rust + tcod_](https://tomassedovic.github.io/roguelike-tutorial/)

---

#### Build your own `Git`

* [**Haskell**: _Reimplementing “git clone” in Haskell from the bottom up_](http://stefan.saasen.me/articles/git-clone-in-haskell-from-the-bottom-up/)
* [**JavaScript**: _Gitlet_](http://gitlet.maryrosecook.com/docs/gitlet.html)
* [**JavaScript**: _Build GIT - Learn GIT_](https://kushagra.dev/blog/build-git-learn-git/)
* [**Python**: _Just enough of a Git client to create a repo, commit, and push itself to GitHub_](https://benhoyt.com/writings/pygit/)
* [**Python**: _Write yourself a Git!_](https://wyag.thb.lt/)
* [**Python**: _ugit: Learn Git Internals by Building Git Yourself_](https://www.leshenko.net/p/ugit/)
* [**Ruby**: _Rebuilding Git in Ruby_](https://robots.thoughtbot.com/rebuilding-git-in-ruby)

---

#### Build your own `Network Stack`

* [**C**: _Beej's Guide to Network Programming_](http://beej.us/guide/bgnet/)
* [**C**: _Let's code a TCP/IP stack_](http://www.saminiir.com/lets-code-tcp-ip-stack-1-ethernet-arp/)
* [**C / Python**: _Build your own VPN/Virtual Switch_](https://github.com/peiyuanix/build-your-own-zerotier)
* [**Ruby**: _How to build a network stack in Ruby_](https://medium.com/geckoboard-under-the-hood/how-to-build-a-network-stack-in-ruby-f73aeb1b661b)

---

#### Build your own `Neural Network`

* [**C#**: _Neural Network OCR_](https://www.codeproject.com/Articles/11285/Neural-Network-OCR)
* [**F#**: _Building Neural Networks in F#_](https://towardsdatascience.com/building-neural-networks-in-f-part-1-a2832ae972e6)
* [**Go**: _Build a multilayer perceptron with Golang_](https://made2591.github.io/posts/neuralnetwork)
* [**Go**: _How to build a simple artificial neural network with Go_](https://sausheong.github.io/posts/how-to-build-a-simple-artificial-neural-network-with-go/)
* [**Go**: _Building a Neural Net from Scratch in Go_](https://datadan.io/blog/neural-net-with-go)
* [**JavaScript / Java**: _Neural Networks - The Nature of Code_](https://www.youtube.com/playlist?list=PLRqwX-V7Uu6aCibgK1PTWWu9by6XFdCfh) [video]
* [**JavaScript**: _Neural networks from scratch for JavaScript linguists (Part1 — The Perceptron)_](https://hackernoon.com/neural-networks-from-scratch-for-javascript-linguists-part1-the-perceptron-632a4d1fbad2)
* [**Python**: _A Neural Network in 11 lines of Python_](https://iamtrask.github.io/2015/07/12/basic-python-network/)
* [**Python**: _Implement a Neural Network from Scratch_](https://victorzhou.com/blog/intro-to-neural-networks/)
* [**Python**: _Optical Character Recognition (OCR)_](http://aosabook.org/en/500L/optical-character-recognition-ocr.html)
* [**Python**: _Traffic signs classification with a convolutional network_](https://navoshta.com/traffic-signs-classification/)
* [**Python**: _Generate Music using LSTM Neural Network in Keras_](https://towardsdatascience.com/how-to-generate-music-using-a-lstm-neural-network-in-keras-68786834d4c5)
* [**Python**: _An Introduction to Convolutional Neural Networks_](https://victorzhou.com/blog/intro-to-cnns-part-1/)
* [**Python**: _Neural Networks: Zero to Hero_](https://www.youtube.com/playlist?list=PLAqhIrjkxbuWI23v9cThsA9GvCAUhRvKZ)

---

#### Build your own `Operating System`

* [**Assembly**: _Writing a Tiny x86 Bootloader_](http://joebergeron.io/posts/post_two.html)
* [**Assembly**: _Baking Pi – Operating Systems Development_](http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/os/index.html)
* [**C**: _Building a software and hardware stack for a simple computer from scratch_](https://www.youtube.com/watch?v=ZjwvMcP3Nf0&list=PLU94OURih-CiP4WxKSMt3UcwMSDM3aTtX) [video]
* [**C**: _Operating Systems: From 0 to 1_](https://tuhdo.github.io/os01/)
* [**C**: _The little book about OS development_](https://littleosbook.github.io/)
* [**C**: _Roll your own toy UNIX-clone OS_](http://jamesmolloy.co.uk/tutorial_html/)
* [**C**: _Kernel 101 – Let’s write a Kernel_](https://arjunsreedharan.org/post/82710718100/kernel-101-lets-write-a-kernel)
* [**C**: _Kernel 201 – Let’s write a Kernel with keyboard and screen support_](https://arjunsreedharan.org/post/99370248137/kernel-201-lets-write-a-kernel-with-keyboard)
* [**C**: _Build a minimal multi-tasking kernel for ARM from scratch_](https://github.com/jserv/mini-arm-os)
* [**C**: _How to create an OS from scratch_](https://github.com/cfenollosa/os-tutorial)
* [**C**: _Malloc tutorial_](https://danluu.com/malloc-tutorial/)
* [**C**: _Hack the virtual memory_](https://blog.holbertonschool.com/hack-the-virtual-memory-c-strings-proc/)
* [**C**: _Learning operating system development using Linux kernel and Raspberry Pi_](https://github.com/s-matyukevich/raspberry-pi-os)
* [**C**: _Operating systems development for Dummies_](https://medium.com/@lduck11007/operating-systems-development-for-dummies-3d4d786e8ac)
* [**C++**: _Write your own Operating System_](https://www.youtube.com/playlist?list=PLHh55M_Kq4OApWScZyPl5HhgsTJS9MZ6M) [video]
* [**C++**: _Writing a Bootloader_](http://3zanders.co.uk/2017/10/13/writing-a-bootloader/)
* [**Rust**: _Writing an OS in Rust_](https://os.phil-opp.com/)
* [**Rust**: _Add RISC-V Rust Operating System Tutorial_](https://osblog.stephenmarz.com/)
* [**(any)**: _Linux from scratch_](https://linuxfromscratch.org/lfs)

---

#### Build your own `Physics Engine`

* [**C**: _Video Game Physics Tutorial_](https://www.toptal.com/game/video-game-physics-part-i-an-introduction-to-rigid-body-dynamics)
* [**C++**: _Game physics series by Allen Chou_](http://allenchou.net/game-physics-series/)
* [**C++**: _How to Create a Custom Physics Engine_](https://gamedevelopment.tutsplus.com/series/how-to-create-a-custom-physics-engine--gamedev-12715)
* [**C++**: _3D Physics Engine Tutorial_](https://www.youtube.com/playlist?list=PLEETnX-uPtBXm1KEr_2zQ6K_0hoGH6JJ0) [video]
* [**JavaScript**: _How Physics Engines Work_](http://buildnewgames.com/gamephysics/)
* [**JavaScript**: _Broad Phase Collision Detection Using Spatial Partitioning_](http://buildnewgames.com/broad-phase-collision-detection/)
* [**JavaScript**: _Build a simple 2D physics engine for JavaScript games_](https://developer.ibm.com/tutorials/wa-build2dphysicsengine/?mhsrc=ibmsearch_a&mhq=2dphysic)

---

#### Build your own `Programming Language`

* [**(any)**: _mal - Make a Lisp_](https://github.com/kanaka/mal#mal---make-a-lisp)
* [**Assembly**: _Jonesforth_](https://github.com/nornagon/jonesforth/blob/master/jonesforth.S)
* [**C**: _Baby's First Garbage Collector_](http://journal.stuffwithstuff.com/2013/12/08/babys-first-garbage-collector/)
* [**C**: _Build Your Own Lisp: Learn C and build your own programming language in 1000 lines of code_](http://www.buildyourownlisp.com/)
* [**C**: _Writing a Simple Garbage Collector in C_](http://maplant.com/gc.html)
* [**C**: _C interpreter that interprets itself._](https://github.com/lotabout/write-a-C-interpreter)
* [**C**: _A C & x86 version of the "Let's Build a Compiler" by Jack Crenshaw_](https://github.com/lotabout/Let-s-build-a-compiler)
* [**C**: _A journey explaining how to build a compiler from scratch_](https://github.com/DoctorWkt/acwj)
* [**C++**: _Writing Your Own Toy Compiler Using Flex_](https://gnuu.org/2009/09/18/writing-your-own-toy-compiler/)
* [**C++**: _How to Create a Compiler_](https://www.youtube.com/watch?v=eF9qWbuQLuw) [video]
* [**C++**: _Kaleidoscope: Implementing a Language with LLVM_](https://llvm.org/docs/tutorial/MyFirstLanguageFrontend/index.html)
* [**F#**: _Understanding Parser Combinators_](https://fsharpforfunandprofit.com/posts/understanding-parser-combinators/)
* [**Elixir**: _Demystifying compilers by writing your own_](https://www.youtube.com/watch?v=zMJYoYwOCd4) [video]
* [**Go**: _The Super Tiny Compiler_](https://github.com/hazbo/the-super-tiny-compiler)
* [**Go**: _Lexical Scanning in Go_](https://www.youtube.com/watch?v=HxaD_trXwRE) [video]
* [**Haskell**: _Let's Build a Compiler_](https://g-ford.github.io/cradle/)
* [**Haskell**: _Write You a Haskell_](http://dev.stephendiehl.com/fun/)
* [**Haskell**: _Write Yourself a Scheme in 48 Hours_](https://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours)
* [**Haskell**: _Write You A Scheme_](https://www.wespiser.com/writings/wyas/home.html)
* [**Java**: _Crafting interpreters: A handbook for making programming languages_](http://www.craftinginterpreters.com/)
* [**Java**: _Creating JVM Language_](http://jakubdziworski.github.io/categories.html#Enkel-ref)
* [**JavaScript**: _The Super Tiny Compiler_](https://github.com/jamiebuilds/the-super-tiny-compiler)
* [**JavaScript**: _The Super Tiny Interpreter_](https://github.com/keyanzhang/the-super-tiny-interpreter)
* [**JavaScript**: _Little Lisp interpreter_](https://maryrosecook.com/blog/post/little-lisp-interpreter)
* [**JavaScript**: _How to implement a programming language in JavaScript_](http://lisperator.net/pltut/)
* [**JavaScript**: _Let’s go write a Lisp_](https://idiocy.org/lets-go-write-a-lisp/part-1.html)
* [**OCaml**: _Writing a C Compiler_](https://norasandler.