Cloudflare Workers Tech Talks in Tokyo #8

Sep 15, 2026 #Workers Tech Talks

Cloudflare Workers Tech Talks in Tokyo #8

We held “Workers Tech Talks in Tokyo #8” on August 27, 2026. This time, it was held as a sub-event of Cloudflare Immerse Tokyo, the biggest Cloudflare event in Japan. And it was the biggest Workers Tech Talks we’ve ever had: about 200 people came, and we had seven great talks. For the first time, the event was also live-streamed on YouTube.

What is Cloudflare Workers Tech Talks?

Cloudflare Workers Tech Talks is an event where developers who are developing using Cloudflare Workers talk about Cloudflare Workers. It has been held multiple times in Tokyo, Osaka, Kyoto, Niigata, Hokkaido, and Fukuoka, and once in Austin, Texas. The feature of this event is that the speakers are free to talk about whatever they want. I often tell the speakers, “Please don’t give introductions like ‘What is Cloudflare Workers?’“. I ask them to talk about whatever they want to talk about.

Venue

The venue was Hall B of TODA HALL & CONFERENCE TOKYO in Kyobashi, Tokyo, the same venue as Cloudflare Immerse Tokyo. Thanks to the Cloudflare Japan marketing team and the event production company for setting this up!

Venue

Attendees

We gathered participants through the event page on connpass.

https://workers-tech.connpass.com/event/400818/

The 280 seats filled up quickly, with 138 more on the waitlist. On the event day, 170 registered attendees showed up, and with guests, staff, and Cloudflare employees included, about 200 people were in the hall.

Live Streaming

This was the first Workers Tech Talks that was live-streamed. TECH WORLD kindly streamed the whole event on YouTube, and the archive is available here:

https://www.youtube.com/live/pDdK_gHt8fQ

Talks

We had seven talks.

Getting Everything Done with Cloudflare

mono

mono talked about running a quiz event portal on Cloudflare and how to fill the gaps where you still need AWS. To call AWS services securely from Workers, he connects them through Cloudflare Tunnel and VPC Service Bindings, with an aws-sigv4-proxy that holds the IAM role on the AWS side. Hybrid architectures between Cloudflare and other clouds are rarely talked about, so this was valuable.

Performance Tuning Containers - Taking on AWS Lambda MicroVMs

sh1ma

sh1ma tackled the cold start of Cloudflare Containers. Both Cloudflare Containers and AWS Lambda MicroVMs run on Firecracker, but Lambda gets VM snapshots on the host side. So he took snapshots from inside the container with CRIU, persisted them to R2, and sped up the restore path with Workers Cache. The latency became much more stable, and as he put it, “it’s practically a win.”

Researching Cloudflare for Enterprise SaaS Broke One of My Architectural Assumptions

わでぃ

わでぃ examined whether you can build SaaS for large enterprises on Cloudflare. Most enterprise requirements are actually covered, but D1’s 10GB limit looked like a blocker at first — until he realized it reflects a design philosophy: give each tenant its own database and scale out, instead of one big shared database. That’s the assumption that got broken.

Live Translation for Events with Laravel × Durable Objects

Ryuta Hamasaki

Ryuta Hamasaki introduced yoyo, a live multi-language translation service for events, and demoed it during his own talk: real-time captions appeared inside his slides and on the attendees’ devices. He builds full-stack with Laravel, but a WebSocket server was the hard part — Durable Objects solved it, with one instance per event and the WebSocket Hibernation API. It handled around 200 connections in the hall without breaking a sweat.

The slides: https://avosalmon.github.io/cloudflare-workers-tech-talks-tokyo/

How Mercari Adopted Cloudflare Images

Boyu

Boyu shared how Mercari replaced its image transformation pipeline with Cloudflare Images. The pricing model — unique transformations are counted once a month no matter how many times they’re accessed — makes costs predictable. They kept S3 as the origin storage and migrated with zero downtime using a dark launch and canary rollout, cutting the image transformation cost by about 65%.

Can I Introduce All Cloudflare Services in 15 Minutes?

Takahashi

Takahashi ran through every single Cloudflare service in 15 minutes, speedrun style. It was also an interactive presentation: the audience could send reactions in real time, and 34,700 reactions came in during the 15 minutes — handled by a single Durable Object. When he hit a service he didn’t know well, “ask Wada-san” became the running joke of the event.

The Essence of Making Things, Seen from an Idol

Karin Miyamoto

The last talk was by Karin Miyamoto, a singer and idol — a former member of Juice=Juice in Hello! Project, now performing solo — and it was her first tech talk ever. She builds web apps for her fans with AI, and she had been using Cloudflare Workers for a while. I had been asking her to speak for some time, and after her story went viral on X in August, it came together right away. I’m grateful to Karin and her manager for gladly accepting. In her talk, she walked us through her workflow: start from “making everyone happy”, check that “no one gets sad”, write a spec within a day of the idea — on her phone, in transit — and use a PC only for building and fixing. Her stack is Workers, D1, R2, KV, and Turnstile. The audience was blown away by how disciplined the whole process was. She also wrote a blog post about the event.

Feedback

I asked the attendees to post on X with the hashtag #workers_tech. So many people posted on the day that the hashtag made it into X’s trending topics. And the buzz didn’t stop there — impressions from people watching the archive kept flowing on the timeline for days after the event. You can see the feedback here:

https://x.com/search?q=%23workers_tech

Some attendees also wrote about the event:

Summary

This was the biggest Workers Tech Talks ever, with about 200 people in the hall and the first-ever live stream. The talks went deep — hybrid architectures with AWS, container performance tuning, enterprise SaaS, live translation with Durable Objects, image delivery at Mercari’s scale, a 15-minute tour of everything Cloudflare, and the essence of making things from an idol’s perspective. Thank you to all the speakers and attendees, to the Cloudflare Japan marketing team and the event production company for the venue and operations, and to TECH WORLD for the live stream!

Here’s the group photo!

Group photo