Kaigi on Rails 2026
Overview
Japan's largest conference for Ruby on Rails users, positioned as "a web technology conference enjoyable for everyone from beginners to experts" with a strong focus on practical, production-grounded sessions. The 2026 edition features a keynote by Rails creator DHH; "The Pragmatic Programmer" author Dave Thomas, announced earlier, is unable to travel to Japan and the organizers are arranging how to proceed. It continues its hybrid format with several hundred on-site attendees.
Foundation
- Founded
- 2020
- Founder
- Founded by community volunteers led by chief organizer Masafumi Okura as a venue for Rails practitioners, distinct from RubyKaigi
Born in 2020 during the COVID-19 pandemic as a YouTube Live online event, driven by the conviction that pausing would make a future restart impossible.
Transition
- 2020 First edition held online on YouTube Live due to the COVID-19 pandemic (about 230 concurrent viewers)
- 2023 First offline edition, shifting to a hybrid format
- 2024 Held at Ariake Central Tower Hall with 692 on-site attendees, about 1.9 times the previous year
- 2025 Held at JP Tower Hall & Conference with keynotes by Kyosuke Morohashi and Samuel Williams
- 2026 Scheduled for Bellesalle Shibuya Garden with a keynote by DHH. Dave Thomas, announced earlier, is unable to travel to Japan and the organizers are arranging how to proceed
Voices
Beyond the sessions themselves, the real value of attending on-site lies in hallway conversations and sponsor booths.
Even as a new-grad engineer, I brought home insights directly applicable to production work.
The conference where you can feel the energy of the Rails practitioner community the most.
Learned from an AI-testing session how semantic HTML shapes AI testability (from Sotaro Fujimaki's report, in Japanese)
Staffed a sponsor booth, connecting with engineers and bonding as a team (from okakee's report, in Japanese)
In the News
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