HalilErenÇelik
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About

I make and lead design from inside the team, not from the outside.

Thirteen years designing and improving products, six of them inside the client’s own product team.

I set the direction, take the decisions with the client from what the work turns up, and review everything that ships. When it helps, an idea goes all the way to a working prototype, a PoC or a demo without leaving my hands.

Halil Eren Çelik Play

Inside OBSS

Since 2019

I am one of the Design Studio’s senior managers, and once I am on an account I work inside the client’s own product team: the same standups, the same backlog, the same release calendar. Design stops being a deliverable and sits alongside the decisions as they are made.

How much of it I carry myself varies from account to account; on some of them it runs the whole way.

How I work

Method

On an account I can carry the work end to end: from analysis and requirements through information architecture, interfaces and the design system, to a working prototype and a proof of concept.

I direct AI rather than brief it: the right skill in the right order, read the report, approve the work or send it back. Nothing here is autonomous. A person stands at every step.

I built my own skill library: DEINS. 15 chapters, 119 services. bugreports was made with it: 122 commits and a demo that runs.

Tools: Figma, Claude Code, ChatGPT, GitHub, Vercel. On measurement I have worked with Amplitude, Mixpanel, Firebase, Microsoft Clarity, Hotjar, Optimizely, Maze, UserTesting and HubSpot. I quote the numbers I measured, and none that I did not.

Where I have worked

2013–today
  • 2019–present

    OBSS

    • 2025–present

      Senior Manager, Design Studio

    • 2021–2025

      Lead Product Designer

    • 2019–2021

      Senior Product Designer

  • 2019

    Sherpa Experience Design Studio

    UX/UI Designer

  • 2018–2019

    Migros

    Senior Product Designer

  • 2017–2018

    Saran Holding · Tuttur.com

    Product Designer

  • 2015–2017

    Supplementler.com

    Product Designer

  • 2013–2014

    TMOBTECH

    UX/UI Designer

  • 2013

    İkipixel Bilgi Teknolojileri

    UX/UI Designer

  • 2011–2012

    Project House / Havas Worldwide

    Young Gun Intern · Digital Design Intern

You can write to me about the work, or about the things I make.

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