About
Built at the
intersection of design
and development.
The studio
Sedaiia is a one-person boutique web studio.
Sedaiia is a one-person boutique web studio founded by John Patrick Koosman. We sit at the intersection of design and development — building things that hold up visually and technically.
The focus is on aesthetic and creative niches: brands, clinics, artists, and founders who care about how things look and how things work. Not one or the other.
Based in the Netherlands. Working with clients internationally.
Founder
JP Koosman
Founder & developer
Design & visual art
Foundation in composition, colour theory, and visual communication.
Tattoo artist
Surrealism and conceptual art. Sharpened the eye for detail, aesthetics, and what makes something feel right.
Vibe coder & studio founder
Combining design intuition with AI-assisted development to build refined digital products.
The path from tattoo artist to web developer isn't as strange as it sounds. Both are about taking something abstract — an idea, a feeling, a brand — and translating it into something tangible that holds up under scrutiny.
The shift to tech came naturally: the same principles apply. Visual hierarchy, whitespace, proportion. The difference is the medium.
Sedaiia exists because most web studios either build beautifully but can't handle technical complexity, or build technically but don't care enough about how it looks. The goal is to close that gap.
Approach
Design theory
A background in visual art means understanding composition, proportion, and visual weight before touching a line of code. The result: interfaces that feel considered, not assembled.
Vibe coding
AI-assisted development is part of the workflow — not as a shortcut, but as a tool that lets a single person build with the output of a small team. Speed without losing the eye.
One person, full focus
No account managers, no handoffs. You work directly with the person building your product. Decisions are made faster and nothing gets lost in translation.