Build Your Own X

Build your own <insert-technology-here>

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
• AI Model
• Augmented Reality
• BitTorrent Client
• Blockchain / Cryptocurrency
• Bot
• Command-Line Tool
• Database
• Docker
• Emulator / Virtual Machine
• Front-end Framework / Library
• Game
• Git
• Memory Allocator
• Network Stack
• Neural Network
• Operating System
• Physics Engine
• Processor
• Programming Language
• Regex Engine
• Search Engine
• Shell
• Template Engine
• Text Editor
• Visual Recognition System
• Voxel Engine
• Web Browser
• Web Server
• Uncategorized

Tutorials

Build your own Distributed Systems

• Java: Building Your Own Kafka-like System From Scratch: A Step-by-Step Guide

Build your own 3D Renderer

• C++: Introduction to Ray Tracing: a Simple Method for Creating 3D Images
• C++: How OpenGL works: software rendering in 500 lines of code
• C++: Raycasting engine of Wolfenstein 3D
• C++: Physically Based Rendering:From Theory To Implementation
• C++: Ray Tracing in One Weekend
• C++: Rasterization: a Practical Implementation
• C# / TypeScript / JavaScript: Learning how to write a 3D soft engine from scratch in C#, TypeScript or JavaScript
• Java / JavaScript: Build your own 3D renderer
• Java: How to create your own simple 3D render engine in pure Java
• JavaScript / Pseudocode: Computer Graphics from scratch
• Python: A 3D Modeller

Build your own AI Model

• Python: A Large Language Model (LLM)
• Python: Diffusion Models for Image Generation
• Python: RAG for Document Search

Build your own Augmented Reality

• C#: How To: Augmented Reality App Tutorial for Beginners with Vuforia and Unity 3D [video]
• C#: How To Unity ARCore [video]
• C#: AR Portal Tutorial with Unity [video]
• C#: How to create a Dragon in Augmented Reality in Unity ARCore [video]
• C#: How to Augmented Reality AR Tutorial: ARKit Portal to the Upside Down [video]
• Python: Augmented Reality with Python and OpenCV

Build your own BitTorrent Client

• C#: Building a BitTorrent client from scratch in C#
• Go: Building a BitTorrent client from the ground up in Go
• Nim: Writing a Bencode Parser
• Node.js: Write your own bittorrent client
• Python: A BitTorrent client in Python 3.5

Build your own Blockchain / Cryptocurrency

• ATS: Functional Blockchain
• Crystal: Write your own blockchain and PoW algorithm using Crystal
• Go: Building Blockchain in Go
• Go: Code your own blockchain in less than 200 lines of Go
• Java: Creating Your First Blockchain with Java
• JavaScript: A cryptocurrency implementation in less than 1500 lines of code
• JavaScript: Build your own Blockchain in JavaScript
• JavaScript: Learn & Build a JavaScript Blockchain
• JavaScript: Creating a blockchain with JavaScript
• JavaScript: How To Launch Your Own Production-Ready Cryptocurrency
• JavaScript: Writing a Blockchain in Node.js
• Kotlin: Let’s implement a cryptocurrency in Kotlin
• Python: Learn Blockchains by Building One
• Python: Build your own blockchain: a Python tutorial
• Python: A Practical Introduction to Blockchain with Python
• Python: Let’s Build the Tiniest Blockchain
• Ruby: Programming Blockchains Step-by-Step (Manuscripts Book Edition)
• Scala: How to build a simple actor-based blockchain
• TypeScript: Naivecoin: a tutorial for building a cryptocurrency
• TypeScript: NaivecoinStake: a tutorial for building a cryptocurrency with the Proof of Stake consensus
• Rust: Building A Blockchain in Rust & Substrate

Build your own Bot

• Haskell: Roll your own IRC bot
• Node.js: Creating a Simple Facebook Messenger AI Bot with API.ai in Node.js
• Node.js: How to make a responsive telegram bot
• Node.js: Create a Discord bot
• Node.js: gifbot - Building a GitHub App
• Node.js: Building A Simple AI Chatbot With Web Speech API And Node.js
• Python: How to Build Your First Slack Bot with Python
• Python: How to build a Slack Bot with Python using Slack Events API & Django under 20 minute
• Python: Build a Reddit Bot
• Python: How To Make A Reddit Bot [video]
• Python: How To Create a Telegram Bot Using Python
• [Python: Create a Twitter Bot in Python Using Tweepy](https://medium.freecodecamp.org/