💎 PicoRuby: Bringing Ruby to Microcontrollers and the Edge of IoT

June 11, 2025

In the world of embedded systems, performance and size matter. But what if we could write microcontroller logic in a language we love — like Ruby? That’s the promise of PicoRuby : a lightweight implementation of Ruby, designed to run on tiny chips like the Raspberry Pi Pico and even the ESP32.

I recently dove into PicoRuby, and it’s one of the most exciting bridges between high-level scripting and low-level hardware I’ve seen in a while.

Let’s Connect!

If you’re passionate about clean architecture, Ruby on Rails, or just want to chat about code, feel free to connect or reach out. I’m always open to sharing ideas, exploring collaborations, or learning something new.

What Is PicoRuby?

PicoRuby is a minimal, efficient Ruby interpreter crafted for embedded environments. Think ~256KB ROM, ~128KB RAM — ideal for boards like the RP2040 (Raspberry Pi Pico) and ESP32 (using ESP-IDF).

Built atop mruby/c, it strips Ruby down to its essentials while preserving its expressive syntax. You can:

• Write Ruby to control GPIO, sensors, and devices
• Compile .rb files into bytecode with picorbc
• Run scripts directly on the board with picoruby
• Use r2p2, a tiny interactive Ruby shell for microcontrollers

And yes — it even runs in the browser via WebAssembly.

Does It Work on ESP32 and Arduino?

ESP32 : Yes, supported through the ESP-IDF framework. There’s even an R2P2 shell version available for ESP32.

Arduino : Not at the moment. PicoRuby doesn’t integrate with the Arduino IDE or AVR boards like the Uno or Mega, as they lack the resources needed. But boards like the ESP32 (using ESP-IDF) or RP2040 are well within scope.

Why Does This Matter?

As someone who enjoys both embedded development and Ruby, this opens up creative possibilities:

• Prototype IoT devices in a friendlier language
• Build Ruby-scriptable custom keyboards
• Run a Ruby REPL on a chip
• Teach Ruby with real-world hardware interaction

It also flips the usual script — instead of forcing C or MicroPython into every MCU project, why not let Ruby in?

Getting Started

To try PicoRuby:

git clone --recursive https://github.com/picoruby/picoruby
cd picoruby/
rake
bin/picoruby -e 'puts "Hello, PicoRuby!"'

Want to deploy to ESP32? Check out picoruby-esp32 for integration with ESP-IDF.

Final Thoughts

PicoRuby is still evolving, but the idea is powerful: give embedded developers and Rubyists a common space to build.

Ruby on microcontrollers isn’t just a dream — it’s compiling and blinking LEDs right now.

Project on GitHub

Let’s bring Ruby to the edge. Literally. #Ruby #IoT #Embedded #Microcontrollers #ESP32 #RaspberryPiPico #PicoRuby #OpenSource #TechTrends