Collapse OS is a Forth-based operating system designed to run on minimal and improvised machines, with the goal of preserving the ability to program microcontrollers through civilizational collapse. It aims to be self-contained, allowing a capable person to build and install it without external resources. The project includes a collection of tools and documentation for editing text and binary contents, compiling assembler source, and reading and writing from various storage devices. Collapse OS can run on machines with very little resources, such as Z80, 8086, 6809, and 6502 devices.