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I’m Denys Boiko, a senior full-stack engineer with 7 years of experience building scalable, high-performance web applications using React, Next.js, TypeScript, and Node.js. I’ve focused on subscription-based products, conversion-first funnels, and analytics-driven development, helping teams ship reliable features end to end—from architecture and API design through code review and release. I’ve delivered production systems integrating Stripe Billing and webhooks, A/B testing, and internationalization across multi-market audiences. I enjoy working in fully remote, cross-functional Agile teams, owning features from requirements to implementation and optimization, and collaborating closely with product managers and designers to improve performance, Core Web Vitals, and SEO.…I’m Denys Boiko, a senior full-stack engineer with 7 years of experience building scalable, high-performance web applications using React, Next.js, TypeScript, and Node.js. I’ve focused on subscription-based products, conversion-first funnels, and analytics-driven development, helping teams ship reliable features end to end—from architecture and API design through code review and release. I’ve delivered production systems integrating Stripe Billing and webhooks, A/B testing, and internationalization across multi-market audiences. I enjoy working in fully remote, cross-functional Agile teams, owning features from requirements to implementation and optimization, and collaborating closely with product managers and designers to improve performance, Core Web Vitals, and SEO.

Denys Boiko

Full Stack Developer, Web Developer, Back-End Developer, +2

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I’m Denys Boiko, a senior full-stack engineer with 7 years of experience building scalable, high-performance web applications using React, Next.js, TypeScript, and Node.js. I’ve focused on subscription-based products, conversion-first funnels, and analytics-driven development, helping teams ship reliable features end to end—from architecture and API design through code review and release. I’ve delivered production systems integrating Stripe Billing and webhooks, A/B testing, and internationalization across multi-market audiences. I enjoy working in fully remote, cross-functional Agile teams, owning features from requirements to implementation and optimization, and collaborating closely with product managers and designers to improve performance, Core Web Vitals, and SEO.…I’m Denys Boiko, a senior full-stack engineer with 7 years of experience building scalable, high-performance web applications using React, Next.js, TypeScript, and Node.js. I’ve focused on subscription-based products, conversion-first funnels, and analytics-driven development, helping teams ship reliable features end to end—from architecture and API design through code review and release. I’ve delivered production systems integrating Stripe Billing and webhooks, A/B testing, and internationalization across multi-market audiences. I enjoy working in fully remote, cross-functional Agile teams, owning features from requirements to implementation and optimization, and collaborating closely with product managers and designers to improve performance, Core Web Vitals, and SEO.

Available to hire

I’m Denys Boiko, a senior full-stack engineer with 7 years of experience building scalable, high-performance web applications using React, Next.js, TypeScript, and Node.js. I’ve focused on subscription-based products, conversion-first funnels, and analytics-driven development, helping teams ship reliable features end to end—from architecture and API design through code review and release.

I’ve delivered production systems integrating Stripe Billing and webhooks, A/B testing, and internationalization across multi-market audiences. I enjoy working in fully remote, cross-functional Agile teams, owning features from requirements to implementation and optimization, and collaborating closely with product managers and designers to improve performance, Core Web Vitals, and SEO.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

Ukrainian

Fluent

English

Intermediate

Russian

Fluent

Work Experience

Full-Stack Developer at Flora Co., Ltd

June 1, 2023 - Present

Developed and maintained production web applications for international clients, primarily subscription-based consumer products with a global user base. Designed and built high-conversion marketing funnels and landing pages (Next.js, React, TypeScript). Implemented end-to-end Stripe subscription flows including Checkout, Billing, and webhooks with localized payment methods across EN/JA/KO/ZH markets. Built A/B testing infrastructure and integrated Mixpanel and GA4 for conversion tracking and product insights. Developed REST APIs with Node.js/NestJS and PostgreSQL, integrating headless CMS via GraphQL and Firebase services. Ensured code quality with unit/integration tests (Jest, React Testing Library) and end-to-end tests (Playwright) within CI/CD, and optimized performance (about 35% page load time improvement) to enhance Core Web Vitals and SEO. Owned features end to end in a fully remote Agile team, including internationalization and localization for multi-region launches.

Front-End Developer at Digital Suits (Web Production Company)

June 1, 2021 - May 31, 2023

Worked on multiple client projects delivering responsive, SEO-friendly web applications. Developed accessible UI components using React, HTML5, and CSS3 for multi-client projects. Implemented CMS-driven websites using a headless CMS approach with GraphQL APIs for content. Improved performance, accessibility, and SEO of existing projects, and ensured cross-browser compatibility and responsive behavior across devices.

Junior Front-End Developer at Stradasol (Web Studio)

September 1, 2019 - May 31, 2021

Built landing pages and small web applications, developing UI components with JavaScript and React. Translated design mockups into production code, fixed bugs, and improved usability.