Crafting Seamless User Experiences

I'm Sergei Serafimovich. A full-stack, product-oriented web designer, and developer, with a primary focus on UX/UI and user interaction. Throughout my career, I have seamlessly integrated design and development roles, enabling me to excel in finding effective solutions for tasks in both fields and comprehending the bigger picture.

My passion for web design, particularly interactive design, ignited with my first encounter with Adobe Flash (it was Macromedia Flash back then). This technology allowed me to enhance both my graphic and programming skills. At the age of 16 I completed my first commercial website for a client.

20 years
of professional experience in web development
Front-end, back-end, SQL and NoSQL, frameworks, CI/CD, etc.
I understand the value of a good user experience and know how to create it
I always think from the perspective of product development
  • MAPILab Ltd.

    May 2004 - Oct 2007, Kaliningrad, Russia

    MAPILab is one of leading software development company on the market of software products for Microsoft Outlook, where I held the dual role of designer and web developer. In 2005, I designed and programmed the company website, which has been operational with minor changes for an impressive 15 years. Additionally, I created several niche product websites, a couple of online mini-games for promotional campaigns, and tons of UI graphics for software products and marketing materials.

  • Pixidio

    Dec 2007 - Dec 2010, Kaliningrad, Russia

    Together with a few friends, I co-founded Pixidio, a small studio dedicated to creating high-quality websites. We successfully developed corporate websites for local companies, including car dealers, restaurants, and factories. Our commitment to great design quality and perfectionism set us apart in the industry.

  • United World Capital

    Dec 2010 - Sep 2011, Limassol, Cyprus

    I began at United World Capital as a designer and web developer and eventually progressed to the role of head of development. This international fintech company provided me with invaluable experience. During my tenure, we built several internal products, including a new referral program, a redesigned company website, and initiated various IT infrastructure changes.

  • Rukuku

    Sep 2011 - May 2012, CA, United States

    As the CTO, I was invited to join Rukuku, a startup focused on building a Learning Management System. Despite having a different vision for the future product compared to the product owner, we managed to build a multi-user real-time drawing whiteboard and a prototype for online course creation during our collaboration.

  • Freelance

    May 2012 — Jul 2015

    I was working on a couple of projects as a freelance designer and developer. Including crypto markets, online stores, portals etc.


    Jul 2015 - Jul 2017, Warsaw, Poland

    OKPAY was an international money transfer and payment service provider. I initially cooperated with them on a freelance basis from their company founding and later joined them full-time. In my role, I was responsible for enhancing user experience on both the client's side and back-office management panel. During my tenure, we created a new client application, improved the back-office management panel, and updated the corporate website.

  • Qantor

    Jul 2017 - Dec 2022, Moscow, Russia

    At Qantor, we were developing an omni-channel E-COM platform. I started as a senior frontend developer and UX/UI specialist, and as the company grew, I became the CPO and frontend team leader. My responsibilities included overseeing UX/UI designers and frontend developers. The platform encompassed an online store, customer mobile applications, manager panels, applications for couriers, sellers at selling points, and more. My focus was on strategizing the product's growth, finding ways to bring more value to our customers with fewer resources, and enhancing user experience.

  • Octo.Sale

    Jan 2023 — Present, Warsaw, Poland

    Currently, I am working on Octo.Sale, a startup that I co-founded with my friend, who oversees the sales and business aspects. On my side, I handle architecture, UX/UI, programming, and more. The product is currently in beta testing, allowing me some time to participate in other projects.