From design mockup,to production-ready quality.

Sapporo-based coding for landing pages, corporate sites and WordPress.
Figma, XD and image-based designs are all welcome.
Also available: chat UIs and business tools with OpenAI / Claude APIs built in.

LP Coding¥12,000 –
Corporate Site¥20,000 –
WordPress¥25,000 –
AI Integration (chat UI / business tools)¥30,000 –
70%+
Repeat clients
100%
On-time delivery
3–5 days
Avg. turnaround
Portfolio of Kaisei Yasuzaki — Sapporo, Japan
( 01 )

WorksSelected Works

Scope, duration and stack are published for every project to support your decision.

01 / 02
LP Coding (Design → Implementation)
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LP Coding (Design → Implementation)

A landing page implemented with HTML/CSS/JavaScript based on a Figma design mockup. Emphasis on responsive design for PC and mobile, with layouts optimized for visual flow and user attention.

SCOPEFull coding (PC / SP responsive)
DURATION3 business days
STACKHTML ／ CSS ／ JavaScript ／ Responsive Design ／ Figma
View Project
02 / 02
LP Coding (Image-based Design)
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LP Coding (Image-based Design)

Coded a landing page using HTML/CSS/JavaScript based on provided design images. Focused on accurate visual reproduction and readable, maintainable markup.

SCOPEFull coding (PC / SP responsive)
DURATION2 business days
STACKHTML ／ CSS ／ JavaScript ／ Responsive Design
View Project
View all works　→
( 02 )

ServicesServices

Frontend at the core, with AI integration and backend covered end to end.

Frontend Development

Web applications and websites built with a modern frontend stack.

React ／ Next.js ／ TypeScript ／ JavaScript ／ HTML5 ／ CSS3 ／ Tailwind CSS ／ shadcn/ui ／ Responsive ／ SPA / SSR ／ Dashboards ／ Admin Panels

Website Coding

Maintainable, fast-loading code built from your design data.

Coding from Figma ／ Landing Pages ／ Corporate Sites ／ Service Sites ／ WordPress Themes ／ Responsive ／ Animations ／ Performance ／ SEO-aware Markup

AI Feature Integration

AI features built into existing services or new web apps using the OpenAI API and more.

AI Chat ／ Text Generation ／ Summarization ／ AI Search ／ Function Calling ／ Structured Output ／ OpenAI API ／ AI-driven Automation

Web Application Development

End-to-end web application development, frontend through backend.

User Accounts ／ Admin Panels ／ Dashboards ／ Authentication ／ API Development ／ Supabase ／ FastAPI ／ PostgreSQL

Automation & API Integration

Systems that streamline daily operations and integrate external services.

REST API ／ Data Processing ／ CSV ／ Email Delivery ／ Google Services ／ Stripe ／ Workflow Automation

Maintenance & Improvements

Improvements and new features for existing systems.

Bug Fixes ／ UI Improvements ／ Refactoring ／ New Features ／ Performance

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Work FlowWork Flow

Rough estimates are available even before your design is finalized.

01ContactSend your design data or URL. I reply within one business day.
02EstimateFixed price and schedule after reviewing the design. Any extra cost is discussed in advance.
03ImplementationCoding with progress updates and mid-checks.
04RevisionsMinor revisions are free. Specification changes are estimated separately.
05DeliveryDelivery of full data, or deployment to your server.
( 05 )

ProfileProfile

Kaisei Yasuzaki
Kaisei YasuzakiFrontend Developer / Web Coder

Sapporo-based frontend engineer. After working as a contract coder for a web production company, now supporting small businesses as a freelancer — from static coding and WordPress themes to web applications with Next.js / TypeScript and AI feature integration using the OpenAI API.

BASESapporo, Japan (fully remote)
STACKHTML / CSS / JavaScript / TypeScript / Next.js / WordPress / PHP / Python / FastAPI
TOOLSFigma / XD / Photoshop / Git
Full Profile
( Contact )

Let's talk about
your project.

"How much would this design cost?" is enough to start.
Send your design data or URL and you will get an estimate within one business day.

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