The document details Mikhail Bortnyk's project to launch Ruby in a 32-kilobyte environment, exploring the challenges and limitations of using Ruby and mruby for IoT devices. It covers previous attempts, the creation of mruby/c, and the achievements and future goals of the project, including cross-compiling and hardware interaction. Bortnyk expresses gratitude to contributors and outlines his plans for enhancing the project further.

1. LAUNCHING RUBY IN 32
KILOBYTES
MIKHAIL BORTNYK

2. LAUNCHING RUBY IN 32 KILOBYTES
WHO AM I
▸ Mikhail Bortnyk, (not only) Ruby developer
▸ kottans.org co-founder
▸ github: @vessi
▸ twitter: @mikhailbortnyk

3. LAUNCHING RUBY IN 32 KILOBYTES
FOR WHY?
▸ because I can
▸ I love Ruby
▸ interested in IoT
▸ learn more about languages virtual machines
▸ learn more about optimisation
▸ get a touch with a real hardware
▸ I want to get fucking led blinking!

4. LAUNCHING RUBY IN 32 KILOBYTES
OPTIONS I KNEW BEFORE
▸ Ruby
▸ mRuby

5. LAUNCHING RUBY IN 32 KILOBYTES
RUBY
▸ Pros:
▸ full language stack
▸ very long story
▸ most of bugs cleared
▸ I have everyday work experience
▸ Cons:
▸ consumes too much memory (valgrind shows ~9Mb)
▸ too big
▸ platform-dependent
▸ bytecode is very experimental

6. LAUNCHING RUBY IN 32 KILOBYTES
MRUBY
▸ Pros:
▸ relatively smaller
▸ actively supported by @matz
▸ proved builds on bigger MCUs (Raspberry Pi and powerful ChipKIT boards)
▸ code can be compiled into byte code to reduce execution time
▸ Cons:
▸ still consumes too much memory (but only 4% from big Ruby, ~400kb)
▸ has complicated build system
▸ partially connected with filesystem so you can’t use FS-less configurations

7. LAUNCHING RUBY IN 32 KILOBYTES
LIMITATIONS
▸ Result build should:
▸ fit in 32K of RAM
▸ take less than 512K
▸ can operate without file system
▸ It will be good if result build can operate with target’s
hardware

8. LAUNCHING RUBY IN 32 KILOBYTES
FIRST TRY
▸ Author: Doug Bradbury
▸ Date: 19 Dec 2008
▸ Target board: Glomation GESBC-2440
▸ Target params: 400MHz ARM CPU, 128 MB SDRAM, 64
MB FLASH and Linux 2.6.18
▸ Ruby version: 1.8.6-p111

9. LAUNCHING RUBY IN 32 KILOBYTES
NEXT STEP (POSSIBLY NOT VERY ACCURATE)
▸ Author: kyab
▸ Date: 31 Dec 2012
▸ Target board: ChipKIT Max32
▸ Target params: PIC32MX795F512L 80MHz MCU, 128KB RAM, 512KB flash
▸ mRuby version: 1.0.0
▸ Caveats: lost Regexps, reduced heap 16 times (64 objects instead of 1024),
lost Time class, gems are disabled
▸ No REPL, only constant code evaluation
▸ requires MPIDE to cross-compile

10. AND I HAVE
FOUND
LAUNCHING RUBY IN 32 KILOBYTES

11. LAUNCHING RUBY IN 32 KILOBYTES
MRUBY/C PROTOTYPE
▸ Author: Shimane IT Open-Innovation Centre (in reality the
only developer is Kazuaki Tanaka)
▸ First presentation of idea: 11 Nov 2015, on slideshare
▸ I found this presentation and wrote email to achieve very
alpha version: 4 Mar 2016
▸ Project gone opensource: 17 Mar 2016

12. LAUNCHING RUBY IN 32 KILOBYTES
MRUBY/C DESCRIPTION
▸ Written in pure C, Makefiles are used to build
▸ Fits in 16K of memory
▸ Totally lost everything in stdlib, only Array, Float and Object
classes left
▸ More than 40% of VM instructions are not implemented yet
▸ Heap is statically linked (length is configurable in time of
compilation)

13. DEMO TIME
I AM GOING TO COMPILE RUBY AND BYTECODE,
FLASH BOARDS, BLINK LEDS AND LOOK PROUD
FOR NO REASON
LAUNCHING RUBY IN 32 KILOBYTES

14. LAUNCHING RUBY IN 32 KILOBYTES
WHAT HAVE I DID
▸ Added cross-compiling system (stolen idea from
micropython)
▸ Added simple HAL to avoid printf calls and remove libc
dependency (-10kb of flash size)
▸ Fixed lambda support (not totally)
▸ Added constants support

15. LAUNCHING RUBY IN 32 KILOBYTES
WHAT I AM PLANNING TO DO
▸ Add IREP subsequences support (IREP is byte code
sequence)
▸ Add runtime class declaration
▸ Move to dynamic memory management system
▸ Try to port lexer and compiler parts
▸ Try to implement REPL
▸ Try to implement network access (need ESP8266 board!)

16. LAUNCHING RUBY IN 32 KILOBYTES
THANKS SECTION
▸ To Mykhailo Odyniuk: this work would be totally
impossible without him. He provided me two
development boards I used in time of porting
▸ To Shimane ITOC and Kenji Sugihara personally for quick
replies and good presentation
▸ To Kazuaki Tanaka for the great work he did implementing
alpha and beta versions of mruby/c

17. LAUNCHING RUBY IN 32 KILOBYTES
KAZUAKI TANAKA
▸ The guy to say ‘Arigato!’
▸ @kaz0505 on Github
▸ Associate professor at Kyushu
Institute of Technology
▸ Profile on LinkedIn

18. QUESTIONS
AND ANSWERS
LAUNCHING RUBY IN 32 KILOBYTES