X86 DOS OS Builder

PTSource X86 DOS OS Builder is a flexible system creation toolkit designed to help you build minimal custom DOS-compatible operating systems for x86 hardware, based on the Microsoft DOS open-source codebase. It allows developers, educators, and retro-computing enthusiasts to assemble tailored DOS systems by selecting, configuring, and integrating core OS components, device drivers, and utilities. The builder supports customization of the kernel, command interpreter, memory managers, and startup configuration, making it possible to create minimal DOS systems. With a focus on clarity, modularity, and compatibility, the PTSource X86 DOS OS Builder is ideal for experimentation, learning operating system internals, preserving legacy software, and developing specialized DOS distributions for real hardware, emulators, or virtual machines.

Description

The purpose of the PTSource X86 DOS OS Builder is to preserve and study the Microsoft DOS open-source codebase while making it practical and relevant for modern retro-computing, education or research. This project exists to safeguard an important piece of computing history by maintaining compatibility with the original DOS architecture, behavior, and design principles, while carefully and occasionally extending it with optional improvements, fixes or components.

Features

Himem and Emm386

PTSource X86 DOS OS Builder includes standard Himem and Emm386 support and a minimal Himem SDK in C and ASM that allows you to build upper memory aware applications.

UMA Memory

PTSource X86 DOS OS Builder allows memory usage in the upper memory area (UMA) above the 640KB conventional memory limit for device drivers and TSR programs.

Basic Commands

PTSource X86 DOS OS Builder has a basic set of commands. They typically follow a syntax of command options and arguments for file manipulation and system administration.

Applications

PTSource X86 DOS OS Builder supports simple and minimal applications that can be added to the build to increase functionality and productivity according to the builder or user needs.

XDIR Included

PTSource X86 DOS OS Builder includes XDIR, an ultra-compact DOS file manager that fits in just 4 KB, providing fast and efficient directory browsing on even the most limited systems.

EDIT Included

PTSource X86 DOS OS Builder includes EDIT, a minimalist DOS text editor that fits in just 3 KB, designed for quick and fast edits on system files working with extremely limited memory.