08/04/2026 updated
100 % available
Senior Frontend Engineer — React, multi-brand e-commerce & white-label platforms
Leioa (Grand Bilbao), Spain
Only remote
Specialist in System Programming — National Aviation University, Kyiv (2010)About me
Fifteen years in, the same thing still interests me: making a codebase several teams can move in without stepping on each other. I work from near Bilbao, mostly with German and UK teams. I ask a lot of questions early — it's cheaper than rebuilding later.
Tailwind CSSJavaScriptAgile MethodologyHTML5Test AutomationUnit TestingCascading Style Sheets (CSS)Code ReviewContinuous DeliveryContinuous IntegrationE-CommerceNode.jsScrum MethodologyTypeScriptReact.js
I'm a frontend engineer with 15 years of experience, most of it in e-commerce and high-traffic consumer platforms. My specialty is multi-brand and white-label frontends: several brands or tenants served from one codebase, with a shared component and design layer, per-brand theming, and a single build and release pipeline instead of one per brand.
For the last five years I've worked on a React monorepo running four B2B e-commerce brands for a listed German group — shared design system, per-brand theming, and a single Jenkins pipeline. Before that: the multi-tenant side of a high-traffic iGaming platform at Playtech (many operator sites, one codebase), enterprise e-commerce including Salesforce Commerce Cloud (Demandware), and incremental modernization of a 100k+ LOC legacy frontend without pausing feature delivery.
Core stack: React, Redux and Redux Toolkit, Reselect, JavaScript (ES6+), TypeScript, SCSS, Tailwind CSS, Webpack, monorepo tooling, Node.js, REST APIs, JWT.
Testing and delivery: Jest, React Testing Library, Playwright, TestCafe, unit / integration / end-to-end testing, CI/CD with Jenkins, release automation, performance optimization, code splitting.
Ways of working: Scrum and Kanban, sprint refinement, estimation, direct work with stakeholders and tech leads, code review, mentoring and onboarding, technical interviewing. Remote, CET timezone, all working communication in English.
Experience
Professional experience10+ years
Freelancer since2021
Languages
EnglishGoodPolishBasic knowledgeSpanishBasic knowledgeUkrainianNative speaker
Project history
B2B e-commerce group (Germany, listed)
Multi-brand React monorepo: four commerce brands on one codebase, shared component and design layer with per-brand theming, single build and release pipeline. Delivery from planning and refinement through to production, plus the tooling around it — CI, unit / integration / e2e suites, release process.
React, Redux Toolkit, Reselect, SCSS, Tailwind, Webpack, Jest, React Testing Library, Playwright, Jenkins
React/Redux product work alongside a legacy modernization track. Refactored a 100k+ LOC legacy frontend to modern JavaScript incrementally, without pausing feature delivery. Designed and built a reusable React component library adopted across the product. Led a small team of 2–3 developers — refinement, estimates, code review, regular sessions with the client. Set up CI/CD pipelines; mentoring, onboarding, technical interviewing, discovery phase.
React, Redux Toolkit, Styled Components, SCSS
Frontend for a high-traffic, multi-tenant iGaming platform: many operator sites served from one codebase, including the site-proxying modules. Built account flows end to end — registration, authentication, profile, booking — against third-party REST APIs with JWT. Cut page load from 8s to 3s through Webpack code-splitting. Built the team's e2e testing framework and an internal analytics dashboard for managers.
Backbone, React, Redux, Reselect, Underscore, Webpack, Jest