I attended Kaigi on Rails 2026 , held on Friday and Saturday, October 16-17. This was my first time.
Kaigi on Rails started in 2020, which happens to be the same year I began my shift to data engineering (and my wandering). I had been away from Rails development until I joined my current company as a Rails engineer last November, so this was my first time attending.
That said, I’ve barely written any Rails or Ruby since. My current work is mostly improving infrastructure and building development workflows, but that’s another story 😅
Come to think of it, RubyKaigi 2026 in April was also my first since Sendai in 2018.
Overall Impressions
I attended Day 1 in person at Bellesalle Shibuya Garden, and watched Day 2 online.
On Day 1, I got to soak up the atmosphere of the venue and even got a photo with DHH, so I enjoyed the real perks of attending in person.
I skipped the venue on Day 2 because (in my personal experience) it was very cold, the Wi-Fi kept dropping, and the translated subtitles were hard to read. I’m also not great with community events in general 😅
Watching online was a great experience. Here’s how I did it:
- Start a Claude session for each talk
- Keep pasting screenshots of the slides, adding my thoughts now and then
It got a bit lengthy, but I ended up with a decent set of notes I can look back on later.
That said, it’s not very human work, so next time I’d like to automate it, or hope some AI does it for me. Humans should just enjoy each talk.
In that sense, having the slides shared up front makes the talks much easier to follow.
Notes on Each Talk
- Taking care of everything beyond deployment: How we grew Kamal into an internal PaaS
- Kamaly is an internal PaaS (an in-house Heroku) built on top of Kamal
- I’d love an environment like Kamaly, but building one on EC2 instances doesn’t seem like something I could do on the side…
- What I learned from building a scheduled job platform three times: the essential truths
- Slides: 3回つくってわかった、定期実行ジョブ基盤の本質情報 - Speaker Deck
- The point that async jobs and scheduled jobs are different in nature really rang true. Who knows when I’ll get to tackle problems like this…
- Persisting massive data with Rails: Designing for 60 billion rows and fighting the bottlenecks
- Slides: Persisting Massive Data with Rails ~Designing for 60 billion rows, and fighting the bottlenecks~ - Speaker Deck
- A textbook example of problem solving. Excellent!
- Are you making the most of Valkey?
- Slides: その Valkey 使いこなしていますか？ - Speaker Deck
- It finally pushed me to create an issue for migrating from ElastiCache for Redis to Valkey…
- Web Framework Benchmark Battle 2026, Any%
- Slides: Web Framework Benchmark Battle 2026, Any% - Speaker Deck
- If AI keeps improving like this, maybe Spinel will actually be able to convert Rails to C?
- Though there still seem to be plenty of issues, like compilation taking forever (or never finishing at all)
- Solid Queue: two years on Rails
- Slides: Solid Queue: two years on Rails | rosa.codes
- It made me want to stop using Sidekiq (Redis) all over again. Our small team looks after three kinds of databases, and at my age I’m still doing late-night maintenance every month…
Conclusion
I wrote up my notes from Kaigi on Rails 2026.
Next year’s event will be held on November 26-27 at Tokyo Big Sight. I plan to at least watch it online.