Blog - Yusuke Wada

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Cloudflare Workers Tech Talks in Tokyo #6

Cloudflare Workers Tech Talks in Tokyo #6

On September 11, 2025, I held “Cloudflare Workers Tech Talks in Tokyo #6”. This time, the event was special as it was held as part of Cloudflare Immerse, Japan’s largest Cloudflare event organized by Cloudflare Japan. Despite being held on a weekday afternoon, 41 people attended. The event featured diverse talks covering everything from personal side projects to enterprise-grade solutions using Cloudflare Workers.

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, and Hokkaido. 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 TODA HALL & CONFERENCE TOKYO, located in the heart of Tokyo in the Kyoboshi area. It was a brand new and very clean conference facility. While Cloudflare Immerse was held in the main hall and large corridors, our Workers Tech Talks took place in one of the dedicated conference rooms within the facility.

Venue

Attendees

We recruited attendees via the following connpass site.

https://workers-tech.connpass.com/event/363850/

We had 56 registrations with 41 people attending the event. The fact that 41 people attended despite it being held on a weekday afternoon shows the strong dedication of the Workers community in Japan!

Event atmosphere

Timetable

Here is the timetable for the event.

Timetable

Talks

This event was part of Cloudflare Immerse, which made it extra special. The session began with an overview of the Cloudflare Developer Platform by James Todd from Cloudflare. We then had six fantastic talks covering a wide range of topics from personal projects to enterprise solutions using Cloudflare Workers and related technologies.

Building toC Services on a Salaryman’s Allowance: Development Strategy for Scaling with Cloudflare Workers

shinaps

shinaps shared his experience building リピめし, a toC service, on a salaryman’s allowance budget using Cloudflare’s full stack. He demonstrated cost calculations for scaling scenarios, analyzing what happens when the service grows significantly in users. The presentation included an interesting comparison between D1 and KV pricing and use cases, showing how to make cost-effective choices when building on Cloudflare.

The slides: https://speakerdeck.com/shinaps/sararimannoxiao-qian-idezuo-rutocsabisu-cloudflare-workersdesukerusurukai-fa-zhan-lue

Using Cloudflare Workers with Open Source SNS

村上さん

村上さん presented about how Misskey.io uses Cloudflare Workers with Misskey, an open-source decentralized microblogging platform that competes with platforms like X (Twitter). He shared various use cases including caching and security enhancements. One particularly interesting challenge he addressed was the security dilemma of open source: since Misskey’s code is public, security fixes and features are visible to everyone, including potential attackers. His innovative solution was to use Workers as an additional layer that can implement protections and optimizations without exposing them in the open-source codebase.

Distributing Music Notation Fonts (SMuFL) with Cloudflare

Ossamoon

Ossamoon presented a fascinating analysis of font distribution techniques, studying Google Fonts and Cloudflare Fonts services as references. He then demonstrated how to apply these distribution strategies to efficiently serve SMuFL (Standard Music Font Layout) fonts through Cloudflare Workers. This was a unique use case showing how Cloudflare can handle specialized content delivery.

The slides: https://speakerdeck.com/ossamoon/le-pu-huonto-smufl-wocloudflaredepei-xin-suru

The Arrival of True Edge-Native Computing: Full-Stack Edge with Cloudflare Containers

井上寛生

井上寛生 gave an in-depth presentation about building real applications with Cloudflare Containers. He demonstrated a web performance measurement tool that captures how web pages render and converts the captures into videos for viewing - with the video conversion processing happening inside Containers. Beyond the technical implementation, he also shared his positive experiences with the Cloudflare stack’s developer experience.

Getting Started with Cloudflare Browser Rendering Today

itome

itome provided a practical introduction to getting started with Cloudflare Browser Rendering. After explaining the service, he highlighted PDF output functionality for SaaS applications as a key use case and demonstrated converting HTML directly to PDF. In his live demo, he showed how to generate and download an invoice as a PDF.

The slides: https://speakerdeck.com/itome/jin-ri-shi-me-rucloudflare-browser-rendering

Converting Import Tariff Rate Tables into an MCP Server

くりったー

くりったー presented an interesting project addressing a common pain point: finding the right tariff codes for imported goods is extremely tedious work. To solve this, he converted Japan’s import tariff rate tables into an MCP server running on Cloudflare Workers using @hono/mcp as a remote MCP. He demonstrated it by registering it with Claude Desktop and showing how to look up the import tariff code for a MacBook through a simple chat interface.

The slides: https://speakerdeck.com/qlitre/shu-ru-shi-xing-guan-shui-lu-biao-womcpsabahua-sitemita

Feedback

I asked the attendees to post on X with the hashtag #workers_tech. You can see the results below.

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

Summary

Workers Tech Talks in Tokyo #6 was held as part of Cloudflare Immerse. While the main Immerse event focused on business-oriented topics like security and enterprise networking, our Workers Tech Talks maintained its casual, developer-focused atmosphere. I think this experimental approach of running Workers Tech Talks within Immerse worked well.

Special thanks to:

Being part of Cloudflare Immerse gave this event a special significance, and we’re grateful for the opportunity to showcase the vibrant Workers developer community in Japan. The high-quality presentations and engaged audience made this a memorable event for everyone involved.

Thank you to everyone who made this event possible!

Group photo