Kazunari Hara (@herablog)

- Tech Lead and Developer Experts (Web Performance) at CyberAgent, Inc

Twitter / GitHub

I 😍 the Web.


CyberAgent, Inc (2008~)

- A lead of the one of the largest frontend teams (technical lead and management)

- A member of a management team (making technical decision)

- A lead of the frontend recruiting team (planning and interviewing)


- Implement websites with the basic web languages like HTML, CSS and JavaScript

- Make web apps with the modern stacks and frameworks such as TypeScript, React, Next.js, Firebase etc

- Architect various types of web sites/apps such as SSR/SSG/CSR/SPA/MPA, BFF (node.js), micro services etc

- Improve web performance with the browser standard features, cache strategy (CDN, HTTP Headers, Service Workers) and the monitoring tools

- Make accessible components with UI designers

- Improve developer experience with CI/CD, Storybook, lint/test etc.

- Management engineers to help them and to achieve the business goal

- Make technical strategy and its decision with the business team

Products (the latests)

Design System Spindle (2020~)

- A tech lead

- Make some tools such as a UI library and a text linter

- Write a guideline on system performance and user experience

- Maintain the design system with some stakeholders

- Tools (Slack, Figma, Asana, Miro, Firebase, TypeScript, React, CSS, Node.js)

Koe-No-Blog (2019~)

- A tech lead and a product manager

- Develop an accessible and performant web product with some cutting-edge technologies

- Tools (Slack, Sketch, Zeplin, Fastly, Firebase, LitElement, CSS, WebAssembly, Node.js)

Ameba Blog (2016~)

- A tech lead

- Replace some outdated technical stacks to the modern stacks and maintain it

- Make the efficient plans and negotiate it with some stakeholders

- Tools (Slack, Sketch, React, CSS, Node.js, Chef, Docker)

Activities (the latests)

2022年、知っておきたいWebのこと ~ パフォーマンス & セキュリティ ~ (2022)

A talk on some topics related to web performance and web security in 2022 with experts.

『WEB+DB PRESS Vol.127』 (2022)

An article on design system. This article explains how to make own design system with branding as a team, and the useful tooling for expanding the design system.

PWA Night Conference 2021 (2021)

Core Web Vitals in Practice explains all about Core Web Vitals in 2021 such as metrics, tooling and the way to improving them.

Cumulative Layout Shifts in Practice (2020)

An article on web performance. This article explains tips for detecting layout shifts and improving it.

PWA Night CONFERENCE 2020 (2020)

A presentation on making scalable web application using PWA. A related slide "Web App Checklist" is also available.

『WEB+DB PRESS Vol.109 最新CDN入門』(2019)

An article on CDN explaining HTTP headers, web caching and CDN comparison.

The further information is available at my works page.