The purpose of the Smalltalk project is to provide computer support for the creative spirit in everyone. Our work flows from a vision that includes a creative individual and the best computing hardware available. We have chosen to concentrate on two principle areas of research: a language of description (programming language) that serves as an interface between the models in the human mind and those in computing hardware, and a language of interaction (user interface) that matches the human communication system to that of the computer. Our work has followed a two- to four-year cycle that can be seen to parallel the scientific method:

Build an application program within the current system (make an observation)
Based on that experience, redesign the language (formulate a theory)
Build a new system based on the new design (make a prediction that can be tested)

This repository contains a step-by-step guide that teaches how to create a simple operating system (OS) kernel from scratch. I call this OS Raspberry Pi OS or just RPi OS. The RPi OS source code is largely based on Linux kernel, but the OS has very limited functionality and supports only Raspberry PI 3.

Each lesson is designed in such a way that it first explains how some kernel feature is implemented in the RPi OS, and then it tries to demonstrate how the same functionality works in the Linux kernel. Each lesson has a corresponding folder in the src directory, which contains a snapshot of the OS source code at the time when the lesson had just been completed. This allows the introduction of new concepts gracefully and helps readers to follow the evolution of the RPi OS. Understanding this guide doesn’t require any specific OS development skills.

For more information about project goals and history, please read the Introduction. The project is still under active development, if you are willing to participate - please read the Contribution guide.