Uxn is a tiny, portable 8‑bit virtual machine designed by Hundred Rabbits (Devine Lu Linvega & Rekka) for “human‑scale” computing: small programs, minimal dependencies, and long‑term maintainability.

Key ideas:

• Architecture: 64 KB address space; two 256‑byte stacks (working and return); byte‑oriented instructions with composable mode bits (short/word, keep, return) to alter operand size, stack selection, and whether to preserve the top of stack.
• Instruction set: compact stack machine ops (stack shuffling, arithmetic, logic, comparison), memory access, literals, and flow control (jumps/subroutines). Devices are accessed via DEI/DEO (device in/out) rather than syscalls.
• Devices (Varvara spec): memory‑mapped I/O blocks implemented by the host (emulator/port). Common ones include System, Console (text I/O), Screen/Sprite (graphics), Mouse/Controller (input), Time, File, and Audio.
• Tooling:
  • uxnasm: macro assembler producing .rom files from Uxntal (.tal) source.
  • uxnemu: SDL-based emulator implementing Varvara (graphics/audio/input).
  • uxncli: headless VM (useful for console apps and scripts).
  • Ports exist for many platforms; codebase is small and easy to embed.
• Language: Uxntal is a minimalist, postfix stack assembly with labels, macros, and a simple include system. Programs interact with devices by writing to their ports.
• Strengths: tiny codebase, deterministic behavior, easy to port, no external dependencies, great for small tools, demos, and creative coding.
• Limitations: 64 KB memory, minimal runtime (no GC/threads), limited standard library—most facilities are “by device.”

Typical uses:

• Little GUIs and editors, pixel/sprite games, trackers, toys, and generative art.
• Educational projects to learn stack machines and low‑level design.
• Long‑lived, archivable software with simple build/run story.

Getting started:

• Clone and build: github.com/hundredrabbits/uxn
• Read the Varvara device spec and Uxntal docs on the Hundred Rabbits wiki (xxiivv).
• Assemble and run: uxnasm program.tal program.rom; uxnemu program.rom (or uxncli for headless).
• Explore the example ROMs and source in the repo to see device usage patterns.

Good references:

• Uxn overview and Varvara device spec on the Hundred Rabbits wiki (xxiivv).
• The uxn GitHub repository’s README and examples.
• Community tutorials and small projects demonstrating Uxntal patterns.

If you tell me your target platform and what you’d like to build (CLI tool, tiny game, visual demo), I can outline the device ports you’ll need and a minimal Uxntal structure to start from.