Keynote Speakers

  • Yusuke Endoh

    Yusuke Endoh


    'A full-time MRI committer at Cookpad Inc. He has been interested in testing, analyzing, abusing of Ruby. He is an advocate of "transcendental programming" that creates a useless program like this bio. (`_`)'.yield_self{|s|eval(t=%q(puts"'#{s.sub(?_,?_+?_)}'.yield_self{|s|eval(t=%q(#{t}))}"))}
  • Chris Seaton

    Chris Seaton


    Chris is a Researcher (Senior Staff Engineer) at Shopify, where he works on the Ruby programming Language, and a Visitor at the University of Manchester. He was formerly a Research Manager at the Oracle Labs Virtual Machine Research Group, where he led the TruffleRuby implementation of Ruby, and worked on other language and virtual machine projects. Before this he completed a PhD at Manchester where he researched programming languages and irregular parallelism.
  • Yukihiro "Matz" Matsumoto

    Yukihiro "Matz" Matsumoto


    The Creator of Ruby


  • Benoit Daloze

    Benoit Daloze


    Benoit Daloze is the TruffleRuby lead. He has contributed to many Ruby implementations, including MRI, TruffleRuby and JRuby. He is the maintainer of ruby/spec, a test suite for the behavior of the Ruby programming language.
  • CRuby Committers

    CRuby Committers


  • Daniel Magliola

    Daniel Magliola


    Life-long coder, expert procrastinator, and occasional game programmer obsessed with code performance and weird Lego machinery.
  • Hiroshi SHIBATA

    Hiroshi SHIBATA


    A member of Ruby core team. He maintains RubyGems, Rake, rdoc, psych, ruby-build, etc. and He is an administrator of ruby-lang.org and supports to develop the environment of Ruby language. He is also Executive Officer in GMO Pepabo, Inc. His most interest things are “Productivity” He believes, there's business value in fun. The team member happiness can make valuable products.
  • Hitoshi HASUMI

    Hitoshi HASUMI


    Programmer of Monstarlab in Shimane Development Branch
  • ITOYANAGI Sakura

    ITOYANAGI Sakura


  • Jeremy Evans

    Jeremy Evans


    Jeremy Evans is a Ruby committer who focuses on fixing bugs in Ruby. He is the lead developer of the Sequel database library, the Roda web toolkit, the Rodauth authentication framework, and many other Ruby libraries. He is the author of "Polished Ruby Programming". He is the maintainer of Ruby ports for the OpenBSD operating system.
  • Josef Haider

    Josef Haider


    Josef Haider is the creator and maintainer of TRegex, a regular expression engine used in TruffleRuby and other Truffle languages.
  • Kenta Murata

    Kenta Murata


    A full-time OSS developer at Speee Inc. I'm a committer of Apache Arrow and CRuby. I'm currently focusing on making Ruby a data-science-ready programming language.
  • Kevin Newton

    Kevin Newton


    Kevin is a staff engineer at Shopify, based out of Boston, Massachusetts. He is passionate about music and open-source software.
  • Koichi ITO

    Koichi ITO


    Koichi ITO is a member of RuboCop core team and Engineering Manager of ESM, Inc. He is a longtime practitioner of Ruby/Rails application development with eXtreme Programming.
  • Koichi Sasada

    Koichi Sasada


    Koichi Sasada is a programmer, mainly developing Ruby interpreter (CRuby/MRI). He received Ph.D (Information Science and Technology) from the University of Tokyo, 2007. Now he is still working on MRI development at Cookpad Inc. He is also a director of Ruby Association.
  • Mari Imaizumi

    Mari Imaizumi


    Software engineer at ESM, Inc.
  • Martin J. Dürst

    Martin J. Dürst


    Martin is a Professor of Computer Science at Aoyama Gakuin University in Japan. He has been one of the main drivers of Internationalization (I18N) and the use of Unicode on the Web and the Internet. He published the first proposals for DNS I18N and NFC character normalization, and is the main author of the W3C Character Model and the IRI specification (RFC 3987). Since 2007, he and his students have contributed to the implementation of Ruby, mostly in the area of I18N.
  • Masataka Kuwabara

    Masataka Kuwabara


    A maintainer of RBS. Works for Bit Journey, inc.
  • Masatoshi SEKI

    Masatoshi SEKI


    Masatoshi Seki is a Ruby committer and the author of several Ruby standard libraries including dRuby, ERB, and Rinda. He’s an expert in object-oriented programming, distributed systems, and eXtreme programming. He has been speaking at RubyKaigi every year since 2006 when the Kaigi first started. He is also Senior Engineer at Canon Medical Systems corp.
  • Mat Schaffer

    Mat Schaffer


    I'm a volunteer with Safecast.org, an SRE with Elastic and a resident of Yamanashi, Japan. I've been working in Ruby since 2006 and authored a number of Ruby tools & resources including knife-solo.
  • Matt Valentine-House

    Matt Valentine-House


    Matt has been working with Ruby in various capacities since 2007, but hasn't previously ventured behind the scenes into it's implementation. He is currently a Senior Developer at Shopify working in the Ruby Infrastructure team. When he's not scratching his head over segmentation faults he can be found brewing beer and building mechanical keyboards.
  • Mauro Eldritch

    Mauro Eldritch


    Mauro Eldritch is an Argentine Hacker & Speaker, Founder of BCA and DC5411. He was a Speaker at DEF CON (six times!), ROADSEC (LATAM’s biggest security conference), DEVFEST Siberia, DragonJAR Colombia (biggest spanish-speaking conference in LATAM), P0SCON Iran, Texas Cyber Summit and EC-Council Hacker Halted among other conferences (25+). He worked as a Cyber Security Architect for different Governments and Companies.
  • Maxime Chevalier-Boisvert

    Maxime Chevalier-Boisvert


    Maxime Chevalier-Boisvert obtained a PhD in compiler design at the University of Montreal in 2016, where she developed Basic Block Versioning (BBV), a JIT compiler architecture optimized for dynamically-typed programming languages. She is currently leading a project at Shopify to build YJIT, a new JIT compiler built inside CRuby.
  • Mike Dalessio

    Mike Dalessio


    Mike has been contributing to Ruby open source since 2006, most notably as the maintainer of Nokogiri. He's currently working at Shopify helping lead the Ruby and Rails Infrastructure team, and previously helped lead the Cloud Foundry open source PaaS project for VMware and Pivotal. He likes coffee, intimate chats, and long walks, and has been known to combine all three.
  • Misaki Shioi

    Misaki Shioi


    Web application developer who loves Ruby & is curious about Web. Member of Asakusa.rb & Fukuoka.rb.
  • Nick Schwaderer

    Nick Schwaderer


    Nick is a Senior Production Engineer at Shopify. He digs into Ruby lore frequently with the PastRubies newsletter. Nick has worked on projects with Ruby to help forecast pain for individuals with chronic illness and assist in communications during a natural disaster.
  • osyo



    Super Engineer Cat.
  • Peter Zhu

    Peter Zhu


    Peter is a Ruby core committer and Production Engineer at Shopify. He is passionate about open-source software and is fascinated by the unknown.
  • Richard Schneeman

    Richard Schneeman


    Schneems is an open-source junkie that loves community building. He created and maintains CodeTriage.com, a tool for helping people contribute to open-source. When he's not working on that you might find him building developer tooling at Heroku or working on his own OSS contributions. He is in the top 50 Rails contributors and is an accidental maintainer of Sprockets and Puma. Last time he checked, he had over a 1.2 billion library downloads on RubyGems.
  • Satoshi "moris" Tagomori

    Satoshi "moris" Tagomori


    OSS developer/maintainer: Fluentd, Norikra, MessagePack-Ruby, Woothee and many others mainly about Web services, data collecting and distributed/streaming data processing. Living in Tokyo.
  • Shugo Maeda

    Shugo Maeda


    The Creator of Textbringer, a Ruby committer, Director of Network Applied Communication Laboratory, and Secretary general of the Ruby Association
  • Sutou Kouhei

    Sutou Kouhei


    He is a free software programmer and the president of ClearCode Inc. He is also the namer of ClearCode Inc. The origin of the company name is "clear code". We will be programmers that code clear code as our company name suggests. He is interested in how to tell other programmers about how he codes clear code.
  • Takashi Kokubun

    Takashi Kokubun


    Optimizing Ruby's JIT compiler. Staff Software Engineer at Treasure Data.
  • Tatsuya Sonokawa

    Tatsuya Sonokawa


    Tatsuya Sonokawa is a programmer developing medical devices at Canon Medical Systems, team Seki. He has been learning Ruby from Seki since 2019.
  • Uchio KONDO

    Uchio KONDO


    A Plain-Old Rubyist, ex-local organizer of RubyKaigi 2019. Creator of Haconiwa, RbBCC and Purua. Lives in Fukuoka - the "coast" city of "west" Japan, works at GMO Pepabo, Inc. as a DataOps/Dev Productivity Engineer. Interests: Systems Programming, Linux Kernel, Containers, Rust and mruby. Big fan of Duolingo (:es: :fi: :ko: :zh: learner, diamond leaguer), Zumba freak.
  • Ufuk Kayserilioglu

    Ufuk Kayserilioglu


    Ufuk is the Production Engineering Manager of the Ruby Infrastructure and Ruby Types teams at Shopify and brings over 20 years of industry experience to the company for the adoption of better Ruby tooling and practices. He currently works remotely from Cyprus where he lives with his beloved wife and wonderful daughter.
  • Vinicius Stock

    Vinicius Stock


    Vinicius Stock is a Senior Software Engineer at Shopify working on improving typing and tooling for Ruby. During the last 5 years, Vini has been writing Rails applications, contributing to the Ruby open source space and blogging about his learnings. Originally from Porto Alegre, Brazil, he is based in Toronto, Canada with his wife Vanessa.
  • Yusuke Nakamura

    Yusuke Nakamura


    Web application developer working in Tokyo as a freelance.
  • やもり



    My name is Hiroki Mori. やもり(YAMORI) is my network nicname. It is Yet Anothor MORI. I was started computer with i8080 at 1980. This is made by solder. My first UNIX is 4.3 BSD on OMRON LUNA at 1988. I still use FreeBSD now. I work on ZRouter.org development. This is build environment for small mips module by FreeBSD. I will talk another approach for small mips module.
  • 蒼時弦也



    I use "Aotokitsuruay" as my ID in Taiwan open source community. I am the technical director at 5xRuby Co., Ltd. and the co-founder at Open Unlight. As an active member of the open-source community, I have a lot of talks, experience in the Ruby language, and have contributed to the Ruby source code. Have development experience of the global logistics system, mobile game server, streaming video system, security training system, and IoT.