Available to hire
I’m Celina Koekenbier, a Product Designer with strong frontend expertise who designs and builds digital products end-to-end, bridging user needs, business goals, and technical constraints. My background as a tech founder and frontend developer helps me ship polished experiences that balance user value with real-world constraints from Graphic design to webdesign and Frontend Development.
I thrive in cross-functional, international teams but am also great at working “solo”, I’m a collaborative problem solver who emphasizes accessibility, design systems, and scalable front-end architectures. I’m excited about AI-assisted design, generative workflows, and continuous learning to deliver intuitive products.
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Language
Dutch
Fluent
English
Fluent
Spanish; Castilian
Fluent
Catalan; Valencian
Advanced
Work Experience
Frontend Developer at Publicis Groupe / Digitas Pixelpark
January 1, 2024 - September 18, 2025Frontend Developer, UI/UX designer, Android & IOS App, graphic designer, marketing and social media manager for MagLes Match App. Delivered pixel-perfect, high-performance web solutions for major German clients, including DocMorris, Astara, and Nahkauf. Learned and implemented Thymeleaf, Rust, and Leptos to meet client needs in complex projects.
CEO / CMO / Designer at Slim Media S.L.
January 1, 2019 - September 18, 2025Graphic and web designer for a great variety of clients designing websites logos, flyers, packaging, magazines, etc.
Freelance Graphic & Web Designer at Insight design
January 1, 2019 - September 18, 2025Designed a complete website prototype in Adobe XD and developed it from scratch, resulting in a modern, fast, and user-friendly site. (Temporary contract for Maternity cover)
UI/UX Frontend Developer at Microgestió Premium Apple Reseller BCN
January 1, 2020 - September 18, 2025Modernized a legacy Flash/ActionScript product into a responsive, mobile-friendly application, greatly improving usability and accessibility. Created custom UIs and contributed to the Vue 3 next-generation platform, enhancing scalability, performance, and maintainability.
Frontend Developer at MEDIFY IBERIA SL
January 1, 2025 - PresentFrontend: JavaScript (ES6+), Vue.js, React, HTML5, CSS3, SCSS, Responsive Web Design, REST APIs; UI/UX: Design Systems, Prototyping (Figma, Adobe XD, Sketch), Web Accessibility (WCAG); Other Tech: Git, MongoDB, Express.js, Node.js, Agile, Scrum, Thymeleaf, Rust, Leptos. Certifications: Web Accessibility Certification, Scrum for Developers, Git Certification.
Frontend Developer at Medify Iberia
January 1, 2025 - PresentDesigned and adapted user interfaces for a health care app, improving clarity and usability and supporting onboarding of a major new client. Modernized a legacy Flash/ActionScript app into a fully responsive web app, improving usability on mobile devices. Contributed to migration of the app to Vue 3, creating reusable UI components.
Frontend Developer at Publicis Groupe / Digitas Germany
January 1, 2022 - December 31, 2024Implemented user interfaces for large-scale web platforms using Vue.js, React, and modern JS practices. Focused on accessibility, performance, and responsive design across remote teams.
Front End Designer at Mikrogestió Apple Premium Reseller
January 1, 2020 - August 31, 2020Designed and built a new front-end for a reseller, delivering a mobile-friendly experience and aligning UI with brand guidelines. Improved conversion and usability during the contract period.
UI/UX Designer & Co-founder at Slim Media
January 1, 2015 - December 31, 2019Co-founded and designed UX for digital products; led UX design, app testing, social media and marketing campaigns; built reusable UI components in collaboration with external developers.
Visual Designer at Insight Design
January 1, 2006 - December 31, 2019Designed logos, visual assets, magazines and websites for various Dutch and Spanish clients; created digital marketing content and brand visuals; collaborated with clients to create cohesive visual identities.
Frontend Designer at Microgestió Apple Premium Reseller
January 1, 2020 - August 1, 2020Designed and built a new website from Adobe XD prototypes using Vue.js; developed responsive marketing emails; created UX visuals and content for digital and offline marketing campaigns.
Digital Designer & Frontend Developer at Insight Design
September 1, 2025 - PresentDelivered end-to-end UI/UX solutions and high-fidelity prototypes for startups and SMEs. Built responsive and performant web applications using HTML, CSS, JavaScript, and Vue.js. Created scalable design systems and component libraries bridging design and development. Applied UX research and Design Thinking to meet WCAG 2.1 accessibility standards and improve conversion.
Frontend Developer / UI/UX Engineer at Medify Iberia S.L.
March 1, 2025 - August 31, 2025Modernized a legacy Flash/ActionScript product into a responsive web application. Designed and implemented custom healthcare interfaces tailored to client requirements. Co-built scalable Vue 3 components for the new app. Optimized mobile-first healthcare workflows across platforms.
Frontend Developer / UI/UX Engineer at Publicis Groupe / Digitas Germany
January 1, 2022 - July 31, 2024Developed high-traffic web interfaces for international brands including DocMorris, Astara, and Nahkauf. Worked with Thymeleaf, Rust, Leptos, and Vue.js. Translated Figma designs into pixel-perfect, performant, and accessible digital products.
Designer & Frontend Developer (Maternity Cover) at Microgestió Premium Apple Reseller
April 1, 2020 - November 30, 2020Redesigned website and created UI prototypes in Figma, translating them into Vue.js code. Defined information architecture and navigation flows. Designed and coded responsive, cross-client compatible HTML email campaigns. Managed all design and frontend workflows during maternity cover.
Product Designer & Co-founder at Slim Media (MagLes Match)
February 1, 2015 - September 30, 2019Co-founded and scaled a safety-focused dating app. Led full-cycle UI/UX design for iOS and Android platforms. Designed invitation-only security features and improved retention through data-driven iteration. Participated in Conector Startup Accelerator and secured ENISA funding.
Founder & Editor-in-Chief at MagLes Magazine
February 1, 2012 - September 1, 2019Founded the first Spanish-language magazine for LBT women. Scaled from digital platform to nationwide print publication. Built a community through partnerships and advocacy. Directed editorial strategy and brand evolution into a tech startup.
Freelance Graphic & Web Designer (Early Career) at Insight Design
January 1, 2006 - November 30, 2021Delivered end-to-end graphic and web design for print and digital products. Designed brand identities, editorial layouts, and packaging from concept to production. Managed print-ready production and digital mockups.
Education
Full-Stack JavaScript Development (MERN) at Ubiqum Code Academy
January 11, 2030 - September 18, 2025Spanish Language at Enforex
January 11, 2030 - September 18, 2025International Studies at Graphic Lyceum Amsterdam
January 11, 2030 - September 18, 2025Graphic Design & Concept at Graphic Lyceum Amsterdam
January 11, 2030 - September 18, 2025Web Accessibility at World Wide Web Consortium (W3C)
January 11, 2030 - December 23, 2025Full-Stack JavaScript & MERN at Ubíquum Code Academy, Barcelona
January 11, 2030 - December 23, 2025Spanish Language at Info Rex International (Barcelona)
January 11, 2030 - December 23, 2025Graphic Design & Concept at Graphic Lyceum Amsterdam
January 11, 2030 - December 23, 2025Web Accessibility at World Wide Web Consortium (W3C)
January 11, 2030 - December 23, 2025Full-Stack JavaScript & MERN at Ubiqum Code Academy
January 11, 2030 - December 23, 2025Graphic Design & Concept at Graphic Lyceum Amsterdam
January 11, 2030 - December 23, 2025Spanish Language at Info Rex International (Barcelona)
January 11, 2030 - December 23, 2025Web Accessibility at World Wide Web Consortium (W3C)
January 11, 2030 - January 11, 2026Full-Stack JavaScript & MERN at Ubiqum Code Academy
January 11, 2030 - January 11, 2026Graphic Design & Concept at Graphic Lyceum Amsterdam
January 11, 2030 - January 11, 2026Master Gen AI for Creatives at Founderz School & Microsoft
January 1, 2026 - February 13, 2026Vibe Coding with Cursor IDE at IT Academy Barcelona Activa
January 1, 2025 - February 13, 2026Git Certification at Udemy
January 1, 2025 - February 13, 2026Figma UI UX Design Advanced at Udemy
January 1, 2025 - February 13, 2026SCRUM Gestión Ágil de Proyectos con SCRUM desde CERO at IT Academy Barcelona Activa
January 1, 2024 - February 13, 2026Frontend Development with Angular at W3Cx (World Wide Web Consortium)
January 1, 2021 - February 13, 2026Web Accessibility Certification (WCAG 2.1 / 2.2, ARIA, Semantic HTML) at Ubiqum Code Academy
January 1, 2019 - February 13, 2026JavaScript & MERN Stack at Enforex Barcelona
January 1, 2019 - February 13, 2026Spanish Language at Enforex Barcelona
January 1, 2003 - January 1, 2003Graphic Design & Concept Development at MediaCollege Amsterdam
January 1, 1997 - January 1, 2001Qualifications
Web Accessibility Certification
January 11, 2030 - September 18, 2025Scrum for Developers
January 11, 2030 - September 18, 2025Git Certification
January 11, 2030 - September 18, 2025Web Accessibility Certifications & Courses (W3C)
January 11, 2030 - December 23, 2025Full-Stack JavaScript & MERN
January 11, 2030 - December 23, 2025Spanish Language Studies
January 11, 2030 - December 23, 2025Graphic Design & Concept
January 11, 2030 - December 23, 2025Web Accessibility (W3C)
January 11, 2030 - December 23, 2025Full-Stack JavaScript & MERN (Ubiqum Code Academy)
January 11, 2030 - December 23, 2025Graphic Design & Concept (Graphic Lyceum Amsterdam)
January 11, 2030 - December 23, 2025Spanish Language (Info Rex International, Barcelona)
January 11, 2030 - December 23, 2025React - Next - Redux
January 11, 2030 - December 23, 2025Vibe Coding Course or IDE - Cibernarium
January 11, 2030 - January 11, 2026Advanced Figma
January 11, 2030 - January 11, 2026React - Next - Redux
January 11, 2030 - January 11, 2026Scrum for Developers
January 11, 2030 - January 11, 2026Git Certification
January 11, 2030 - January 11, 2026Angular IT Academy
January 11, 2030 - January 11, 2026Master Gen AI for Creatives
January 1, 2026 - February 13, 2026Vibe Coding with Cursor IDE
January 1, 2025 - February 13, 2026Git Certification
January 1, 2025 - February 13, 2026Figma UI UX Design Advanced
January 1, 2025 - February 13, 2026SCRUM Gestión Ágil de Proyectos con SCRUM desde CERO
January 1, 2024 - February 13, 2026Frontend Development with Angular
January 1, 2021 - February 13, 2026Web Accessibility Certification (WCAG 2.1 / 2.2, ARIA, Semantic HTML)
January 1, 2019 - February 13, 2026JavaScript & MERN Stack
January 1, 2019 - February 13, 2026Spanish Language
January 1, 2003 - January 1, 2003Graphic Design & Concept Development
January 1, 1997 - January 1, 2001Industry Experience
Software & Internet, Media & Entertainment, Professional Services, Retail, Education, Computers & Electronics, Healthcare
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
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