Your startup dream,
started in 4 hours
A developer of 23 years and startup specialist finishes your SaaS, marketplace or company dashboard in 4 hours
Monetization, marketing and operations consulting come along the way
Let an agency build it and came away disappointed? Unhappy with the service you run today?
We'll make it better in 4 hours
Refund if you are not satisfied · Lowest price guarantee
This is the level of launch-ready service you get
Trusted by
KT
FastCampus
Getcha
PeopleFund
Loadcomplete
Lotte Innovate
SoccerBee
HelloNature
아프니까 사장이다
BuildingRoad Group
SNUH
KHUMC
KSA
GSIPA
FUNDA
ReviewNote
TABA
Gemblo
Grandmachan
Hauoli
Farmkit
Million Pick
E2E Health
153 Design
What changes in four hours
Today
After the session
Today
You have an idea, but nothing to show an investor or a customer.
After the session
You have a launched service. You can take customers, take payments, and start the business.
Today
Changing one line of copy means finding a developer.
After the session
You can edit it yourself. No code needed — you change copy and screens directly.
Today
You keep revising the plan with no way to know what is right.
After the session
You see how real users behave. You can decide what to build next from data.
Today
You do not know how to get the word out.
After the session
You learn a marketing approach that fits your business. You also get a shot at being featured on our 22K-subscriber YouTube channel.
Today
Even once it is built, it lives on the agency's server and accounts.
After the session
You own the source code and the copyright. You can keep running it without us.
What you receive
- A live service
- An admin panel
- The full source code
- A signed copyright transfer
- The know-how to edit it
What you get in four hours
How it works
One 4-hour session
We build together with the screen shared. Planning through live deployment happens in that session.
Per session
Included
- First product: plan, design, build, deploy
- User-facing app or web plus an admin panel
- A sanity check on the business itself
- Content generation and workflow automation
- A look at grant programs you could apply to
- Operations and marketing strategy
- Launch, payments, and server walkthrough
- A handover you can build on yourself
Not included
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App Store / Play Store submission on your behalf
We walk you through the release process step by step, but the review submission and developer account stay in your name.
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Brand design work
You get screens that are ready to use. Logos, brand guidelines, and multiple design directions to compare are out of scope.
-
Ongoing operations after the session
Server monitoring and customer support are not included. If you need them, it continues as an annual maintenance contract.
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Approval from outside institutions
We prepare payment-gateway applications and grant paperwork with you, but the decision belongs to that institution.
-
Anything beyond four hours
If the scope does not fit one session, we split it into more sessions.
Thirty minutes is enough to decide
If we cannot show you a satisfying result within 30 minutes of starting, we refund everything, no questions asked.
This is not for everyone
A real-time build means sitting together for four hours, so the situations it fits are specific.
A good fit if
-
You know what you want built
Not a finished spec — just being able to say who it is for and what it does is enough.
-
You need it live this month
A grant deadline, an investor meeting, a competitor launch — a reason it cannot wait.
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You can clear four hours
We build with your screen shared. Someone who can make decisions on the spot needs to be there.
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You plan to run it yourself
You take over and keep improving it. The source code and the copyright both go to you.
Not a good fit if
-
You are still looking around
If there is no date yet, start with the free material and come back when there is.
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The budget is not ready
One session is $3,200. If that is a lot at this stage, building it yourself through the courses is the better route.
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You want to hand it off entirely
A real-time build is made together. If you want to delegate all of it, this is not the right format.
-
You want ongoing operations covered
The scope ends at build and handover. Server care and customer support are a separate contract.
It is fine if now is not the time
Try it yourself, and come back if you need to.
Built personally by James, a 23-year veteran
A full-stack AI & dev expert with 8.5B KRW cumulative revenue and 350+ shipped projects handles everything from planning to deployment
James (Sunghoon Lee)
23-Year Full-Stack AI · Dev Expert
₩2B annual revenue, ₩8.5B cumulative — hundreds of complex platforms shipped
Using AI agents to handle more work than a company of dozens of employees
3,000+ students trained in development, vibe coding, and entrepreneurship
Repeat judge for government startup programs and hackathons
heyjames YouTube
22K+ Subscribers
최근 추천 영상
Founders who commission a live build get a guest appearance and promotion on the 22K-subscriber heyjames channel.
Why you should work with James
Built hundreds of startup platforms — combining a developer's eye with a founder's perspective.
Ran an agency to 8.5B KRW in revenue. Sales, contracts, operations — all hands-on experience.
Through hundreds of projects, James has built deep domain knowledge across legal, tax, real estate, advertising, education, startups, monetization, programming, infrastructure, and AI.
You needed months, tens of thousands of dollars, and a team of several developers.
One 23-year veteran builds the same scope with you in 4 hours, at 1/10 the cost.
23 years in Korea's startup industry. Through Insomnia agency, James has shipped over 350 platforms.
- Startups
- Getcha · HelloNature · FastCampus · LoadComplete · KCD · PeopleFund · SoccerBee + 200 more startups
- Enterprise
- KT · Cheil · POSCO · Lotte Department · Lotte Data
What you leave with
- You can build features and operate the service yourself.
- A scope that used to cost 10× — now in your hands within 4 hours.
- Optional follow-up sessions and a maintenance subscription to grow further.
No result in 30 minutes? Full refund.
We prove it with results, not promises. If we can't show you a satisfying result within the first 30 minutes of the session, you get a full refund — no questions asked. That's how confident we are.
In the first 30 minutes, James plans with you, builds an initial version, and deploys it to a test server — all live on screen.
Plan and prioritize
We listen to your idea and decide together what to build first.
Build the first version
We demo Claude Code prompts and skills on screen, building a working first version.
Deploy to a test server
We deploy to a real domain right there and confirm it's working.
Live demo and know-how, all at once
A rough idea is enough. James asks the right questions and demonstrates Claude Code prompts and skills on screen as we build together.
All the essentials in one session
Auth, profile edit, account deletion, terms, privacy policy, admin pages, email sending, analytics, stats, and SEO — all covered in one session.
By the end of the session
You'll be able to build features and operate the service yourself. A scope that used to cost 10× to outsource, delivered in 4 hours.
What's next
Additional sessions
When you want to expand into new features, you can add as many follow-up sessions as needed.
Maintenance subscription
Ongoing support to handle whatever comes up while you operate the service.
James keeps shipping products
Not just teaching or consulting — James ships his own products the same way. Every one is fully built including the admin panel and ready to operate.
What a founder who built it with us says
Real words from a founder who built their own service with HeyJames.
“What amazed me most was being able to build just by describing what I wanted, even without knowing how to code. Whenever I left a request, an updated result came back in no time.”
“Every question got answered right away, so I never got stuck or left wandering on my own.”
“I signed up drawn by the promise of seeing results fast — and it really was that fast, so I was glad I chose this. Other places quoted timelines that were just too long.”
“Everywhere else quoted tens of millions of won, while this was only a few million — at first I was skeptical. It exceeded my expectations and I was thrilled.”
“The moment I saw the result, 'wow, this is great' just came out. Even the landing page came out clean and polished — I was surprised.”
“It had even built parts I hadn't thought of. You get not just what you asked for, but more.”
“Working directly with the founder meant no middlemen and instant communication — that earned my trust.”
“The progress was organized so systematically that I could always see at a glance what was done and what was left.”
“I've already shown it to peers in my startup program, telling them 'you should try this.' I confidently introduced it as something that builds your prototype fast.”
“I don't want this to be a one-off — I'd love to keep going with maintenance and further development. That's how much I trust them.”
“Seeing the result made me so eager to launch that I could hardly wait. That's how excited I am.”
“They handed over the source code and even walked me through how to run it, so I ended up editing and deploying changes myself. It's not a dead-end handoff — I can keep growing it on my own, and that's what I loved most.”
What people ask on the call
Why this price? I have heard cheap outsourcing is risky.
Risky cheap work has three tells: a quote produced without asking about requirements, work starting with no contract, and no plan for after launch. We do the opposite on all three. The reason it costs less is simple. With AI and 23 years of practice, the same work takes less time. It is not a price built by cutting wages or handing the work to cheaper hands — it is what happens when the same result genuinely takes fewer hours. $3,200 covers one 4-hour session. If the scope is too large for one session, we split it across sessions at the same rate. Nothing gets added later.
Can it really be done in four hours?
Core features, payments included, usually land within one or two sessions. When a session ends, the result is deployed and reachable at a domain. Not a demo — a service that runs. It works because we narrow the scope first. Early in the session we agree on priorities together and build the most important thing first. If it will not fit in four hours, we say so at the start and split it. You can judge in 30 minutes. Something is running on screen by then, and if you are not satisfied, it is a full refund.
Can I trust the quality of AI-written code?
In the AI era, review matters more than writing. On top of automated tests, a developer with 23 years of experience reviews it directly, and we check it together on the shared screen during the session. You test it yourself, right there. Most issues that surface are fixed in one or two prompts. More importantly, you watch it being built — which is a fundamentally different kind of verification than receiving a finished deliverable and judging it cold. The stack is a proven full-stack framework (Ruby on Rails). It is standard code, not tied to a platform, so another developer can pick it up and read it.
Who owns the source code and the copyright?
You do, all of it. You receive the full source code and can connect it to your own GitHub repository so the change history lives with you too. Separately from handing over files, the contract states the copyright transfer explicitly. Receiving files and receiving rights are legally different things. Under case law, if the contract has no transfer clause the copyright stays with the developer. Check that clause wherever you go. We work only from a standard contract, which spells out copyright and source transfer, acceptance criteria and timing, defect-repair scope, and the change-request process.
What if I do not like the result?
You can cancel any time within 30 minutes of the session starting, and we refund the full amount. No questions. We set it at 30 minutes because by then something is already running on screen — enough to tell whether this way of working suits you. It is the opposite of a structure where you only find out at the very end and refunds are hard. After delivery, defect repair is free for six months. If something that was supposed to work does not, we fix it at no cost.
What happens after it is built?
The default is handing it over so you can run it yourself. If you want, we set up an AI coding environment (Claude Code) on your machine and train you on it. Without studying code, you can handle copy and screen changes yourself through prompts. If that is not for you, it continues as an annual maintenance contract. We handle change requests and questions against a time balance, and when the contract ends you get handover documentation. If you hire a developer, we brief them on the code too. Even when the engagement ends, the service stands on its own. Copyright, source code, server and domain accounts, deployment docs — all transferred into your name, so it runs without us. Not creating dependence is the principle.
Hear it from a client who built with heyjames
From the first request to the final product — a client shares the experience in their own words.
Why James builds on Ruby on Rails
While JS full-stacks like React, Next, Vercel, and Supabase evolve in fragments, Ruby on Rails has settled into the strongest single-person full-stack for shipping a SaaS end-to-end. The gap only widens in the AI era.
The stack AI builds fastest
- Same feature in roughly 1/5 the code
- More fits in the AI's context — fewer hallucinations and rework
- Faster and more accurate than React + Express + Prisma
Code volume to deliver the same feature
One Rails instead of 100 libraries
- Long AI calls and email run on Solid Queue
- Realtime chat and notifications via built-in WebSocket
- Subscription billing and recurring jobs on a built-in scheduler
- Frontend, DB, cache, and storage in one package
One server runs the whole SaaS
- One VPS in Seoul region runs DB, files, scheduler, and web
- Operate for around $10/month until traffic really grows
- No stacked bill for Vercel + Supabase + Upstash + Resend + S3
Operations setup
- • Everything inside one VPS
- • Vercel (hosting)
- • Supabase (DB · auth)
- • Upstash (queue · cache)
- • Resend (email)
- • S3 (storage)
Out of the npm supply-chain blast radius
- Fewer dependencies = smaller attack surface
- Auth · CSRF · SQL injection · sessions handled by the framework
- API keys stay server-side — never leak to the client
Average dependencies in production
Rails
~30 gems
React / Next
~1,500 npm
One person ships end-to-end
- Rails: 1 person owns product → ops
- JS full-stack: FE · BE · DevOps · DBA split
- The secret behind shipping in 4 hours
Roles required
Rails
👤 × 1
JS full-stack
👤 × 4
Same shape one year later
- Rails conventions: same for 20 years
- Code AI wrote a year ago still composes cleanly today
- Successor handoff takes a fraction of the time
How often core frontend tooling churns
MVC · ActiveRecord · ERB
Router · State · Bundler
Rails 로 만들어진 회사들
AI 시대에도 살아남은 풀스택 — 세계 최대 코드 호스팅부터 국내 대표 서비스까지, 같은 프레임워크 위에서 운영되고 있습니다.
-
GitHub
세계 최대 코드 호스팅
Microsoft 75억 달러 인수 -
Shopify
글로벌 이커머스 플랫폼
시총 약 1,500억 달러 -
Airbnb
글로벌 숙박 공유
시총 약 850억 달러 -
Stripe
온라인 결제 인프라
기업가치 약 700억 달러 -
Twitch
라이브 스트리밍
Amazon 9.7억 달러 인수
-
당근마켓
지역 기반 중고거래
기업가치 약 3조 원 -
마이리얼트립
여행 예약 플랫폼
누적 거래액 1조 원+ -
리멤버
비즈니스 네트워크
드라마앤컴퍼니 · 가입 400만+ -
업비트
암호화폐 거래소
두나무 · 국내 1위 거래소 -
잡플래닛
기업 리뷰 · 채용
기업 리뷰 600만+ 건
Can you build apps too?
Yes — as hybrid apps.
We build the mobile web first, then package it as an app. The single build runs across desktop browsers, mobile browsers, iPhone apps, and Android apps with the same UX and feature set. No need to build for four environments separately.
Toss and Karrot, along with many leading services in Korea and abroad, are already built and operated as hybrid apps.
Desktop Web
Mobile Web
iPhone App
Android App
Native features still work
Push notifications, in-app purchases (App Store / Play Store), camera and contacts access — anything that only works inside a mobile app is implemented alongside.
Packaging tech
We pick from Hotwire Native, Flutter, or React Native — whichever fits the service best.
Why non-developers can't get to launch
There's a repeating pattern to why people learn vibe coding but never actually launch. Breaking that pattern is at the core of how James works.
Common failure pattern
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People keep adding features without setting any operating policies.
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Security and risk reviews are skipped entirely.
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Multiple features get built at once, conflicting with each other.
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Each feature moves on before being reviewed or covered by tests.
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Ideas get explained to the AI in whatever order they come to mind.
How we actually work
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We split the work into the right unit and build one step at a time.
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After each build, we review the code and write tests.
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Risky pieces get verified in a simple structure first, then merged into the main flow.
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Each new feature is layered on top of verified ones for safe growth.
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We analyze the plan and structure it technically so the AI understands it clearly.
Take it over and run it yourself with vibe coding
We hand the deliverable over to your team and guide you so you can modify and operate it yourself with vibe coding.
Source code repository
We hand over the entire source code, repository and all — it's fully your asset from day one.
AI agent setup & usage
From installing the AI agent that edits your code to using it in practice.
Editing code & deploying
The full flow of changing features yourself and deploying to production.
Testing & detailed code walkthrough
How to test, plus a detailed explanation of the code's structure and behavior.
Database specification
The data structure and table relationships, documented and handed over.
You do not have to decide today
See how someone works before you hire them.
YouTube channel
Long-form walkthroughs of real builds, plus startup and monetization thinking. The fastest way to see how we work.
Free guides
Vibe coding, security, Git, databases — the places people get stuck when building it themselves.
Read guidesCourses
For people who would rather build it themselves. Doing it without us is a perfectly good option.
Browse coursesFind grant programs
Search startup support programs open right now. Many clients pay for their build with grant funds.
Search programsFrequently Asked Questions
The questions clients ask most often before commissioning a build.
Our plan isn't finalized yet — can we still commission a build?
Yes. With AI, the cost of writing code has dropped so much that building an MVP first and refining it in use beats perfecting a spec up front. Features are prioritized and built in stages, and if you know your own business, that is the plan — no separate product planner needed.
Does changing things later cost a lot?
Unlike traditional outsourcing, there's no per-change quote. Because we bill by build complexity and difficulty, you don't have to lock the scope in advance — request and change as much as the time allows, and a reference screenshot is usually all we need to build the screen you want.
How does the contract work?
We only work with a standard written contract. It explicitly covers copyright and source-code transfer, acceptance criteria and review period, the scope of free defect repairs, and the change-request process. Under court precedent, copyright stays with the developer unless the contract says otherwise — wherever you commission work, check for that clause. We include it up front.
What about maintenance after launch?
Development is followed by an annual maintenance contract. Change requests and questions are handled against a time balance, we hand over documentation when the contract ends, and if you hire a developer we'll walk them through the code.
What's the difference between defect repair and maintenance?
Defect repair means fixing, free of charge, anything that was contracted to work but doesn't — provided for 6 months after delivery. New features and improvements are maintenance (paid), with scope, response time, and cost defined in writing before we proceed. Keeping the two separate in the contract is what prevents disputes later.
We don't know how to code — can we edit and operate it ourselves later?
Yes. If you'd like, we set up an AI coding environment (Claude Code) on your machine and train you to use it. No need to study code — copy and screen tweaks can be done with prompts, and anything you get stuck on we sort out together in a session.
Do you build in payments too?
Yes. As a Toss Payments partner we help you apply with the sign-up fee waived, and we implement both one-time and subscription payments. We build against test keys first — swap in your keys and real payments go live.
Can the server handle it when users grow?
We build so that a server costing a few dollars a month handles tens of thousands of users. Because we use a proven full-stack framework instead of stacks whose bills explode with usage, you simply upgrade the server step by step as you grow.
Can we pay with government startup-program funds?
Yes. We prepare the paperwork such programs require — outsourcing contracts, development plans, and completion reports. With extensive experience both judging and delivering government-funded projects, we work to each agency's requirements. We also issue the full set of settlement documents — statements of work, photo-documented inspection reports, and tax invoices — and handle prior-approval and multiple-quote procedures for larger contracts.
Can it integrate with systems we already use, or an engine we built ourselves?
Yes. We support outbound API calls, webhooks fired on events, and connecting your own engine (Python or otherwise) as a separate API server. We can also build a public API with an OpenAPI schema so AI agents like Custom GPT Actions can call your service.
Where are our data and uploaded files stored?
The initial version is stored in dedicated storage on servers we operate in Korea. When you move to production, we migrate the database and file storage to cloud infrastructure you own (e.g. AWS Seoul region).
Is data safely separated per company or per customer?
Yes. The app is designed as a multi-tenant system where every query is scoped to the signed-in account's company, blocking cross-company access at the code level. If you need a physically separate database or server, we can set that up as a dedicated build.
When we delete a file or record, is it really deleted?
Yes. Deleting removes both the database record and the actual file in storage immediately. Backup retention and disposal policies are designed around your privacy requirements.
Can the HEY JAMES team see our data?
The service has no screens for browsing client data, and server access is used only for operations such as incident response. Once you migrate to infrastructure you own, your data is entirely under your control.
How are secrets like API keys managed?
Sensitive values such as API keys and passwords are managed with encrypted configuration files (Rails encrypted credentials), with the decryption key stored separately. Nothing is stored in plain text in the database or source code.
When we go to production, do we own the domain, database, and storage?
Yes. The domain is registered under your name, and the database, file storage, and backups are all migrated to your own accounts. Test accounts and demo data are cleaned up at handover.
Can non-developers get consulting?
Absolutely! Many non-developers inquire about creating services using AI and no-code tools.
What topics can I consult on?
You can consult on IT startups, MVP development, AI usage, vibe coding, freelance/agency operations, marketing, and more.
How do refunds work?
If you request a refund within the first 30 minutes of your session, we'll fully refund you. After that 30-minute window, refunds aren't available.
How are sessions conducted?
Sessions run online via Google Meet. Once payment goes through, your confirmation email includes the Meet link. You can share your screen and walk through actual code, designs, or business materials together.
How should I prepare before a session?
Nothing is required, but if you jot down the problem you want to solve, your questions, and your current situation, we can dive much deeper within the limited time. Feel free to share repo links, planning docs, or links to competing products in advance.
Can I reschedule or cancel?
You can reschedule up to 24 hours before the session — contact support and we'll move you to another available slot. No-shows or cancellations within 24 hours may not be eligible for a refund.
Is what I share confidential?
Anything you share during a session — business ideas, code, planning materials — is never shared externally. If you need a separate NDA signed, just request it ahead of time.
Can I ask follow-up questions after the session?
Short follow-up questions by email (james@heyjames.ai) are welcome and answered as time allows. For deeper follow-ups, please book another consulting slot. Repeat clients often opt for the 10-session sprint package.
Do you offer team or company-wide consulting?
Yes — group consulting for startup teams, agencies, and in-house dev teams runs on a custom quote. Reach out via support with your team size, topic, and preferred schedule and we'll put together a plan.
Can I pay with a government startup grant?
Yes! Many clients have paid using grants from programs such as the Youth Startup Academy, Pre-Startup Package, Early-Stage Startup Package, Social Enterprise Support, and the Re-Challenge Package.
Start now — the easy way in
One focused 4-hour session with a 23-year veteran — from plan to live deployment.