Open to collaboration13 years building products

I turn ideas into
shipped, revenue-ready products

I'm not a freelance-for-hire engineer. I'm most useful as a technical cofounder who can turn direction into a real product fast. If you understand market, users, and growth, we can get an MVP live and testing revenue in a week.

Build a revenue productSee shipped proofContact me
13 years buildingOne person product teamLive apps + web productsMVP possible in a week
Why me
Traction / Speed / Ownership
English
0→1
Solo shipping
I can handle design, engineering, and launch myself
7d
MVP speed
With a clear wedge, I can get a testable version live in a week
Own
High ownership
I work for product outcomes, not ticket completion
Proof

Not credentials. Shipped products with real use cases.

LinguaStage
Live on the App Store

An AI education product built for subscriptions and long-term iteration, not a throwaway demo.

HeyGigaFile
Password sharing + auto delete

A lightweight web product for fast file transfer with password protection and 7-day cleanup built in.

Company analysis tool
AI-driven B2B workflow

Turns company data, risk judgment, and prompt routing into a usable decision product.

Fit

Who I want to build with

The goal is to build 0→1 products together and validate revenue, not hand over code and disappear.

Good Fit
You understand market, growth, or users and have a direction worth testing
You want long-term leverage, not short-term help
You can help define MVP scope and validate conversion
Not a Fit
No agency work
No short-term contracting
No pure implementation-only support
Edge

Why work with me

I can handle design, engineering, launch, and iteration myself
I know how to turn AI into product behavior, not just API calls
I can keep infra and experimentation costs under control
I think like a builder, not a ticket-closer
Portfolio

Live App Store apps

Browse the shipped work on-site first, then open each app in its own App Store listing.

LinguaStage:JLPT対策アプリ最速で単語を覚える

EducationiPhone / iPad
LinguaStage:JLPT対策アプリ最速で単語を覚える screenshot 1
LinguaStage:JLPT対策アプリ最速で単語を覚える screenshot 2
LinguaStage:JLPT対策アプリ最速で単語を覚える screenshot 3
Since Mar 21, 2026App Store
Open in App Store

LinguaStage Bunpō

EducationiPhone / iPad
LinguaStage Bunpō screenshot 1
LinguaStage Bunpō screenshot 2
LinguaStage Bunpō screenshot 3
Since Mar 24, 2026App Store
Open in App Store

FuriRead - Furigana Reader

EducationiPhone / iPad
FuriRead - Furigana Reader screenshot 1
Since Feb 12, 2026App Store
Open in App Store

Luma - Soundscapes&White Noise

Health & FitnessiPhone / iPad
Luma - Soundscapes&White Noise screenshot 1
Since Jan 10, 2026App Store
Open in App Store

NetLens

Developer ToolsiPhone / iPad
NetLens screenshot 1
NetLens screenshot 2
NetLens screenshot 3
Since Aug 29, 2025App Store
Open in App Store

Cyber Hourglass

EntertainmentiPhone / iPad
Cyber Hourglass screenshot 1
Cyber Hourglass screenshot 2
Cyber Hourglass screenshot 3
Since Nov 12, 2025App Store
Open in App Store

配送追跡ナビ

UtilitiesiPhone / iPad
配送追跡ナビ screenshot 1
配送追跡ナビ screenshot 2
配送追跡ナビ screenshot 3
Since Jul 7, 2025App Store
Open in App Store

法人情報ナビ

BusinessiPhone / iPad
法人情報ナビ screenshot 1
法人情報ナビ screenshot 2
法人情報ナビ screenshot 3
Since Jun 23, 2025App Store
Open in App Store

说日语

UtilitiesiPhone / iPad
说日语 screenshot 1
说日语 screenshot 2
说日语 screenshot 3
Since Apr 4, 2024App Store
Open in App Store
Stack

What I bring to the table

Backend systems

  • •Java / Kotlin (Spring Boot)
  • •GraphQL (Hasura / Pothos)
  • •MySQL / PostgreSQL / Redis
  • •JWT auth / API design

Frontend and mobile

  • •Flutter (iOS / Android / macOS)
  • •React / Next.js
  • •UI design systems

Cloud and infrastructure

  • •AWS / Cloudflare / GCP
  • •Docker / Kubernetes
  • •Cloud Run / Workers

Applied AI

  • •LLM apps (OpenAI / Groq)
  • •Agent systems (MCP / LangGraph)
  • •RAG + vector databases
  • •Prompt engineering
Projects

Live and building product bets

LinguaStage

Japanese learning app

Live on the App Store

An AI-driven JLPT learning platform from N5 to N1 with a custom gamified system and subscription monetization.

FlutterAI ContentSubscriptionsMultilingualApp Store

HeyGigaFile

Fast file sharing on the web

Live on the web

A lightweight web product for temporary file transfer, with password-protected sharing and automatic deletion after 7 days.

WebFile sharingPassword protected7-day auto deleteWebsite

AI Company Analysis System

Risk and profile intelligence

In development

Analyzes company and legal-entity signals, generates AI profiles, and uses prompt routing plus reusable templates.

LLMRedisAI PipelineB2B

Linux Command Learning Game

Developer education product

In design

A game-like terminal learning experience with animation, sound, and progression designed to improve retention.

EducationGamificationDeveloper Tools

AI Agent Team System

Multi-agent CLI

Experimenting

Multiple agents collaborate on tasks with a TUI dashboard, task decomposition, and agent scheduling.

MCPLangGraphCLIAutomation
Current focus

Where I want to build next

AI + vertical products for education, business, and tooling
Sticky lightweight apps and training loops
Local AI with privacy and lower operating cost
Automated product generation across AI, UI, and data
Seeking a cofounder

I build the tech,
you shape the product

I can independently ship the full technical stack from prototype to production. I'm looking for a partner who understands users, product strategy, and go-to-market.

✓Strong product intuition and clear MVP framing
✓Some user insight or market access
✓Can contribute to operations, content, or growth
✓Aligned with AI-first vertical products
Talk by email
Partners

The people I most want to meet

This is not just an investor page. It's a collaboration entry point for people who can move a product forward.

Product / growth cofounders
You understand users, market, positioning, and conversion.
Operator-builders
You can push content, acquisition, channels, and retention.
Early backers / investors
You believe in AI vertical products and want faster experimentation.
Open the partner channel