Looks like you have JavaScript disabled. For the full Twine experience, you will need to re-enable it.

Hello, I’m Zeljko Krsmanovic performing online stores and scalable business solutions. Expertise in Shopify theme and app development, CRO optimization, and end-to-end e-commerce strategy, combining technical excellence with data-driven business insights. Passionate about helping brands grow by building seamless, high-converting e-commerce experiences and long-term digital strategies. If you’re looking for someone who understands both the technical side and the business side of e-commerce—and can turn that into real results—let’s build something that actually grows your revenue.…Hello, I’m Zeljko Krsmanovic performing online stores and scalable business solutions. Expertise in Shopify theme and app development, CRO optimization, and end-to-end e-commerce strategy, combining technical excellence with data-driven business insights. Passionate about helping brands grow by building seamless, high-converting e-commerce experiences and long-term digital strategies. If you’re looking for someone who understands both the technical side and the business side of e-commerce—and can turn that into real results—let’s build something that actually grows your revenue.

Zeljko Krsmanovic

Web Developer, Front-End Developer, Back-End Developer, +2





Hello, I’m Zeljko Krsmanovic performing online stores and scalable business solutions. Expertise in Shopify theme and app development, CRO optimization, and end-to-end e-commerce strategy, combining technical excellence with data-driven business insights. Passionate about helping brands grow by building seamless, high-converting e-commerce experiences and long-term digital strategies. If you’re looking for someone who understands both the technical side and the business side of e-commerce—and can turn that into real results—let’s build something that actually grows your revenue.…Hello, I’m Zeljko Krsmanovic performing online stores and scalable business solutions. Expertise in Shopify theme and app development, CRO optimization, and end-to-end e-commerce strategy, combining technical excellence with data-driven business insights. Passionate about helping brands grow by building seamless, high-converting e-commerce experiences and long-term digital strategies. If you’re looking for someone who understands both the technical side and the business side of e-commerce—and can turn that into real results—let’s build something that actually grows your revenue.

Available to hire

Hello, I’m Zeljko Krsmanovic performing online stores and scalable business solutions. Expertise in Shopify theme and app development, CRO optimization, and end-to-end e-commerce strategy, combining technical excellence with data-driven business insights.

Passionate about helping brands grow by building seamless, high-converting e-commerce experiences and long-term digital strategies. If you’re looking for someone who understands both the technical side and the business side of e-commerce—and can turn that into real results—let’s build something that actually grows your revenue.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Language

English

Fluent

Work Experience

Full Stack Web Developer at Upwork

August 1, 2016 - Present

Upgraded and maintained responsive web applications using HTML, CSS, and JavaScript, improving page load time by 25% and increasing mobile user satisfaction. Optimized frontend interfaces with React and Redux, achieving ~40% faster page rendering. Developed SQL and MongoDB databases, enabling streaming data storage and reducing query response time by ~20%. Collaborated with cross-functional teams across multiple projects.

Shopify Development Consultant | Headless Shopify, AI + Shopify SEO Digital Marketing at Significa

March 1, 2019 - Present

Worked with Significa, a digital product design and development agency, to build award-winning web and product experiences for global clients. Led headless Shopify storefront projects using Next.js, Shopify Storefront API, and GraphQL to deliver scalable, high-performance e-commerce experiences. Integrated AI-driven product recommendations and personalized search features. Improved Lighthouse performance and SEO; connected third-party AI tools to enhance conversions.

Shopify Development Consultant | Headless Shopify, AI + Shopify SEO at Freelance / Shopify

April 1, 2021 - Present

Headless storefront development using Next.js, GraphQL, and Shopify APIs; front-end optimizations; AI-driven product recommendations and personalized search; improved conversions and site performance.

Shopify Storefront Frontend Developer at Significa

March 1, 2019 - Present

Led frontend storefront implementations with Next.js and GraphQL; improved conversion and performance on e-commerce storefronts.

Shopify Storefront Frontend at Significa

March 1, 2019 - Present

Developed and maintained responsive Shopify storefronts, including new storefront front-ends using Next.js and GraphQL; improved performance and UX.

Shopify Storefront Frontend Developer at Campera

January 1, 2020 - Present

Led development and growth optimization of a Shopify-based online store for caravan and camping accessories in Australia. Built high-performance storefronts, structured a scalable catalog (100 SKUs), optimized conversion funnels for high-ticket items, and implemented frontend and UX improvements.

Shopify Storefront Frontend Developer at Flycraft USA

January 1, 2023 - Present

Developed a Shopify storefront for an outdoor brand; improved site performance and usability across devices; enabled efficient product management.

Shopify Ecommerce Strategy & Development at Freelance / Shopify

November 1, 2024 - Present

Led optimization for Shopify front-end storefronts using SSR/CSR; integrated AI-driven recommendations and analytics services; improved SEO and core web vitals.