Available to hire
I’m Martin Contreras, a full-stack engineer with 8 years of experience building e-commerce solutions across AI and CRO-focused projects. I specialize in headless and composable commerce, working with Shopify Storefront APIs (GraphQL/REST), React, Remix, and Node.js to deliver fast, scalable storefront experiences for US and UK clients.
Skills
Language
English
Advanced
Spanish; Castilian
Fluent
Work Experience
Senior Shopify Headless & CRO Specialist at Code up
June 1, 2022 - September 1, 2026Built custom headless e-commerce setups using Shopify Storefront APIs (GraphQL/REST) with React, Remix, and Node.js for US brands and UK enterprise clients. Delivered native extensibility and automation via custom Shopify Functions for dynamic checkout rules, scheduled triggers, and discount logic, while orchestrating backend operational tasks with Shopify Flow. Developed modular, highly customizable Liquid sections and blocks that let marketing teams build landing pages without developer intervention. Engineered full-stack Shopify custom apps using Remix and Node.js, integrating third-party tools, AI solutions, and GA4 analytics. Led technical stakeholder communication in English, aligning implementations to conversion goals.
Senior Shopify Headless & CRO Specialist at Codup
June 1, 2022 - September 1, 2026Built and maintained Shopify headless e-commerce setups for US and UK brands using Shopify Storefront APIs (GraphQL/REST), React, Remix, and Node.js. Implemented native extensibility and automation with Shopify Functions for dynamic checkout rule evaluation, scheduled triggers, and custom discount logic, and used Shopify Flow to automate operational backend tasks. Developed modular, highly customizable Liquid sections and blocks to let marketing teams build landing pages without developer intervention. Engineered full-stack Shopify custom apps with Remix and Node.js, integrating third-party tools, AI solutions, and GA4 analytics, while leading technical communication in English with stakeholders to align delivery with conversion goals.
Full-Stack E-Commerce Developer at Serfe
December 1, 2018 - May 1, 2022Designed and implemented modular Shopify theme and Liquid development supporting highly customizable sections and blocks for marketing landing pages. Focused on performance and quality assurance by optimizing SQL queries, building client-side caching layers, conducting code reviews, and handling cross-browser compatibility across client stores. Partnered with cross-functional teams to improve site speed and Core Web Vitals across multiple storefronts.
Web & Software Developer at Nova CRO
September 1, 2016 - October 1, 2018Developed scalable web applications, RESTful APIs, and microservices using Node.js, Express, JavaScript, and SQL databases. Configured CI/CD deployment pipelines using Docker across AWS, GCP, and Azure to streamline staging-to-production workflows.
Education
Bachelor's degree at National University of La Matanza
June 1, 2013 - June 1, 2018Bachelor's degree at National University of La Matanza
June 1, 2013 - June 1, 2018Qualifications
Industry Experience
Retail, Software & Internet, Computers & Electronics, Professional Services, Other
Skills
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