About — Celis, Seoul
A studio that argues with its work.
Anyone can write a good introduction. Celis is a small team led by its founder, Wanwoo Sim, and the case for hiring us is the set of live URLs on this site — sites and products you can open right now, not screenshots and not a list of claims.
Who you are actually hiring
We are a registered business in Gyeonggi-do, Korea, and the registration details are published below in full — a small studio abroad is worth checking, and we would rather make that easy than hope you skip it.
Your email goes to Wanwoo Sim, the founder, not to a sales queue, and the person who answers is part of the team that builds the work. For a project, senior designers and developers join according to what it needs; nothing is passed downstream to another shop once the contract is signed.
We work async-first — email and shared documents, so every decision and preview exists in writing — and take calls by appointment. Seoul runs ahead of the US and Europe, which means a brief sent at the end of your day is being worked on at the start of ours. Our team has strong working English.
How we work
- 01
One team, start to finish
Planning, design, development, and operation stay with the same team. Nothing is handed to a subcontractor halfway through, so what was agreed at the start is what gets built — and there is one place to ask, not a chain of people relaying messages.
- 02
The right specialists on the project
Senior designers, developers, and planners join according to what the project actually needs. The size of the team flexes; the standard the work is held to does not.
- 03
We stay after launch
Delivery is not the end of the relationship. We work through what comes up in operation and stay available as the technical partner for as long as it is useful to you.
Judge us before you pay us
Hiring a studio on the other side of the world is a leap, so we take the leap out of it. Describe what you need and we build a working preview of one key screen, deployed to a URL you open, before any contract or deposit. You judge the real thing in your browser rather than a proposal deck. We take on a limited number of these each month; if we are full, the reply says so.
Business details
- Registered name
- Celis (셀리스)
- Founder
- Wanwoo Sim (심완우)
- Business registration number
- 278-06-03714
- sww@celis.co.kr
- Registered address
- 4F 402-163A, 16 Sure-ro 116beon-gil, Wabu-eup, Namyangju-si, Gyeonggi-do 12218, Republic of Korea
We invoice from this registered business; payment is a standard international bank transfer.
Start with whatever you have — two sentences or a full brief. You will have a reply within one business day on your clock.