https://github.com/picoruby/picoruby
PicoRuby is the smallest Ruby implementation for one-chip microcontrollers
https://github.com/picoruby/picoruby
microcontroller mruby mrubyc ruby
Last synced: 13 days ago
JSON representation
PicoRuby is the smallest Ruby implementation for one-chip microcontrollers
- Host: GitHub
- URL: https://github.com/picoruby/picoruby
- Owner: picoruby
- License: mit
- Created: 2020-01-18T13:50:52.000Z (almost 7 years ago)
- Default Branch: master
- Last Pushed: 2026-10-10T04:00:05.000Z (22 days ago)
- Last Synced: 2026-10-10T05:15:02.919Z (22 days ago)
- Topics: microcontroller, mruby, mrubyc, ruby
- Language: C
- Homepage:
- Size: 139 MB
- Stars: 1,106
- Watchers: 17
- Forks: 73
- Open Issues: 14
-
Metadata Files:
- Readme: README.md
- License: LICENSE
- Agents: AGENTS.md
Awesome Lists containing this project
README
[](https://github.com/picoruby/picoruby/actions/workflows/c-cpp.yml)
## PicoRuby
PicoRuby is an alternative mruby implementation which is:
- Small foot print (depending on build config)
- RAM: 512 KB or less (PicoRuby with networking)
- RAM: 128 KB or less (FemtoRuby)
- Portable
- Depends on only standard C library such as glibc, Newlib or Newlib-nano, and emcc
- Reference microcontroller boards
- Raspberry Pi Pico 2 W - Arm Cortex-M33, 520 KB RAM, 4 MB Flash with CYW43 network module
- Raspberry Pi Pico - Arm Cortex-M0+, 264 KB RAM, 2 MB Flash
### FemtoRuby?
From version 4.x, we call the artifacts below:
- PicoRuby (used to be MicroRuby) ... mruby VM version
- FemtoRuby (used to be PicoRuby) ... mruby/c VM version
mruby VM version is mainly being developed.
### API documentation with some demo videos
[https://picoruby.org/](https://picoruby.org/)
### Depends on
- [PicoRuby compiler (picoruby/mruby-compiler2)](https://github.com/picoruby/mruby-compiler2) as mruby-compiler
- [Estalloc (picoruby/estalloc)](https://github.com/picoruby/estalloc)
- [Littlefs (littlefs-project/littlefs)](https://github.com/littlefs-project/littlefs)
- [mruby (mruby/mruby)](https://github.com/mruby/mruby)
- [mruby/c (mrubyc/mrubyc)](https://github.com/mrubyc/mrubyc)
### Used by
- [R2P2](https://github.com/picoruby/picoruby/tree/master/mrbgems/picoruby-r2p2): PicoRuby shell system for Raspberry Pi Pico
- [R2P2-ESP32](https://github.com/picoruby/R2P2-ESP32): ESP32 port
- [PicoRuby.wasm](https://www.npmjs.com/package/@picoruby/wasm-wasi): PicoRuby WASI runtime for WebAssembly
- [PRK Firmware](https://github.com/picoruby/prk_firmware): Keyboard firmware for Raspberry Pi Pico
## Testing
For detailed information on testing PicoRuby, refer to the [Testing Guide](docs/testing-guide.md).
### Build
- Prerequisites
- C toolchain
- git
- ruby (should be CRuby 3.4+)
```console
git clone --recurse-submodules https://github.com/picoruby/picoruby
cd picoruby/
git submodule update --init --recursive # If you forgot --recurse-submodules when git clone
rake # same for `rake picoruby:prod`
rake picoruby:debug # for debug build
bin/picoruby -e 'puts "Hello World!"'
```
- Building on a mac
- openssl is not linked in homebrew to avoid mixing with system ssl
- extend the C/LD flags to point to the right locations:
```console
rake LDFLAGS=-L$(brew --prefix openssl@3)/lib CFLAGS=-I$(brew --prefix openssl@3)/include
```
#### FemtoRuby (mruby/c VM version)
```console
rake femtoruby:prod
# or
rake femtoruby:debug
```
#### Cross compilation
See an example: [build_config/r2p2-picoruby-pico2.rb](build_config/r2p2-picoruby-pico2.rb)
### Binaries
`rake` command will make three kinds of executable binary
- bin/mrbc
- `bin/mrbc path/to/source.rb` makes `path/to/source.mrb` that is VM code runs on an mruby-compatible virtual machine
- bin/picoruby
- `bin/picoruby source.rb` executes Ruby just like normal `ruby` command
- `bin/picoruby -e "puts 'Hello1'"` also works
- bin/r2p2
- POSIX version of R2P2 (See [mrbgems/picoruby-r2p2](mrbgems/picoruby-r2p2) for the Raspi Pico edition)
### Acknowledgement
Part of this project was coded by [Monstarlab](https://monstar-lab.com/) with the support of
the Ruby Association Grant Program
[2020](https://www.ruby.or.jp/en/news/20201022)
and
[2021](https://www.ruby.or.jp/en/news/20211025).
See also [picoruby/picoruby/wiki](https://github.com/picoruby/picoruby/wiki).
### Stargazers over time
[](https://starchart.cc/picoruby/picoruby)
### License
Copyright © 2020- HASUMI Hitoshi. See MIT-LICENSE for further details.
Copyright © 2020-2021 Monstarlab. See MIT-LICENSE for further details.