SENIOR ECOMMERCE ENGINEER
Milan Petrovic architecting scalable commerce infrastructure.
Senior developer with 13+ years of experience delivering high-performance headless architecture, complex B2B portals, and custom ERP integrations. I build resilient commerce systems for businesses where the platform is a serious infrastructure decision.
About
Engineering commerce infrastructure for serious scale.
I build Shopify environments for companies where the platform is a critical business decision, not just a storefront. With over 13 years of delivery experience, my focus is the work that unlocks real scale on Shopify Plus: complex B2B portals, custom ERP-synced workflows, and headless Hydrogen storefronts. The integration layer is where most enterprise projects fail, so I architect purpose-built Laravel middleware and Go microservices to ensure data integrity where off-the-shelf tools fall short.
Skills & Tools
The stack I build with
- Shopify Plus
- Shopify B2B
- Headless Commerce
- Hydrogen / Oxygen
- Checkout Extensibility
- Shopify Functions (Rust/WASM)
- Storefront API
- Liquid
- Custom ERP Integrations
- Laravel
- PHP
- Golang
- Node.js
- GraphQL
- REST API
- TypeScript / JavaScript
- React
- Next.js
- Remix.js
- Alpine.js
- Tailwind CSS
- Vite
- PostgreSQL
- Redis
- AWS
- Docker
- CI/CD Pipelines
- Git / Gitflow
- Cursor
- GitHub Copilot
- Claude Code
- Claude Cowork
- Google Antigravity
- OpenAI Codex
- JetBrains AI
- Junie
Work Experience
Where I've made an impact
Founder & Lead Shopify Developer
Surface Commerce Agency
- Owned migration of a legacy Liquid theme to a headless Hydrogen/Oxygen architecture, choosing an incremental cutover that cut mobile LCP from 4.8s to 1.4s and drove +18% PDP conversion.
- Architecting and delivering headless storefront migrations, establishing strong frontend patterns, and conducting technical code reviews for merchants at the headless inflection point.
- Developing a commercial Shopify theme targeting the Theme Store, managing the full product lifecycle from design system to submission requirements.
Senior Shopify Developer
Enkomion
- Led technical delivery on four concurrent Shopify Plus builds (€80k-€350k range) and owned end-to-end delivery on nine DTC builds, consistently shipping on time and within scope.
- Drove a high-impact migration from jQuery to Alpine.js and Liquid components, eliminating 2.1s of render-blocking overhead and lifting median PageSpeed from 48 to 81.
- Designed a self-serve, section-based landing page system that reduced client campaign turnaround from 6 hours to 40 minutes.
Senior Shopify & Fullstack Developer
Planted Foods AG
- Architected the full B2B Shopify Plus implementation end-to-end, earning direct CTO recognition for speed and technical depth on a highly complex feature.
- Drove development of a custom Microsoft Dynamics 365 ERP connector, choosing a purpose-built solution over off-the-shelf middleware to guarantee data integrity and platform reliability.
- Integrated OpenAI GPT and Azure AI across B2B and B2C platforms to deliver advanced product discovery and chat functionality.
Full Stack Developer
Swiss Organic Partners AG
- Designed a full migration from legacy themes to modern architectures, deploying a GitHub-based CI/CD pipeline that eliminated manual release steps and improved platform monitoring.
- Demonstrated technical leadership by establishing rigorous development standards and leading the technical onboarding of an in-house IT specialist.
Freelance Web Developer
Independent Practice
Owned end-to-end delivery of web projects across 8 years of independent practice, deliberately driving a systematic shift from static HTML builds to adaptive CMS architectures. Consistently shipped full project lifecycles on time without a PM layer, selecting the optimal stack to reduce post-launch dependency and grant clients full content autonomy.
Featured Builds
Architectural outcomes
A curated selection of three recent deployments, highlighting high-volume DTC storefronts and unified B2B/DTC architecture.
Enterprise Dual-Channel Architecture
Engineered a dual-channel enterprise architecture for publicly traded powersports manufacturer Massimo Motor (NASDAQ: MAMO). The solution bridges a high-volume Shopify storefront for parts and accessories with a purpose-built Ekho Dealer portal to handle high-ticket vehicle compliance and B2B fleet sales. This separation of concerns enables a frictionless "Click. Ship. Ride." DTC funnel for consumers while maintaining strict titling and dealer-network compliance for vehicles ranging up to $17,999.
Unified Global DTC Infrastructure
Delivered a unified global DTC architecture for German manufacturer LA SIESTA, serving over 100 countries and 10+ currencies from a single Shopify storefront. To drive conversions for highly considered purchases, we embedded custom SPA product quizzes directly into the navigation architecture. Combined with a localized 13-provider payment gateway and color-variant SEO canonicalization, the build elegantly scales their 100-day return promise and sustainability narrative across all international markets without portal fragmentation.
Localized Retail Discovery Architecture
Architected a multi-market DTC experience for Planted, a Swiss food-tech B Corp, supporting localization across five languages with a primary focus on the Swiss market. The core innovation is a custom Single Page Application (SPA) store locator deployed on a dedicated subdomain. This decoupled SPA scales across 7+ countries and 13+ retail chains without impacting Shopify performance. The build also features a custom cart widget calculating real-time CO2 and water savings per checkout.
Continuous Upskilling
Continuous architectural refinement
Treating education as a core engineering requirement to ensure the systems I build rely on the most current, reliable patterns.
Enterprise Commerce
Shopify AcademyMastering headless patterns, Hydrogen/Oxygen deployments, and complex B2B logic straight from official Shopify Plus engineering documentation.
Laravel & Middleware
LaracastsDeep-diving into complex PHP architectures, custom ERP connectors, and AI-augmented Laravel development through Jeffrey Way's rigorous curriculum.
Modern Frontend & AI Workflows
Ecosystem Docs & BeyondDeepening expertise in React and Remix architectures for headless builds, while actively integrating AI-native dev tooling to maximize shipping velocity and frontend performance.
Executive Feedback
Trusted by leadership
Direct perspectives from the CEOs and technical directors I partner with.
I’ve been working with Milan for over a year, and it’s been a productive and genuinely enjoyable collaboration in every respect. Clear communication, reliability, and a shared commitment to quality made the partnership easy from day one. Highly recommended - without reservation!
Milan's quick understanding of our company and customer needs was invaluable. His friendly, collaborative nature, reliability, and sharp focus on priorities made him an asset to our team.
Milan was an invaluable asset to our team as the lead software engineer responsible for developing our website and international e-commerce shop. His reliability and swift execution helped us meet crucial deadlines and implement features that were vital for our business's growth.
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