Open to opportunities

Marc User

@marcuser4

Message

I build end-to-end Rails, React, and AI features that improve products at scale.

United Kingdom

Message

What I'm looking for

I'm looking for a small, product-focused team where I can own features end to end, from schema and backend systems through shipped UI, testing, and deployment.

At Judge.me, I built and ran production LLM features for a Shopify reviews platform serving roughly 700,000 merchants, helping lift trial-to-paid conversion from 12% to 23%. I also led a Vue.js and Rails routing rebuild that reduced CLS from 0.9 to 0.23, migrated Shopify integrations from REST to GraphQL, and cut Vitest CI from around 13 minutes to under five.

I'm currently building Cupbored, a social recipe app with a Rails 8 API, React Native client, Terraform-managed AWS infrastructure, and an asynchronous LLM recipe-curation pipeline. Across fintech, B2B platforms, and e-commerce, I've owned features from schema design through shipped UI, tests, deployment, and mentoring engineers in Rails and query design.

Experience

Work history, roles, and key accomplishments

Current

Software Engineer, Ruby on Rails

Current

Cupbored

May 2026 - Present (4 months)

Building Cupbored, a social recipe app with a Rails 8 API and React Native client, including an LLM batch pipeline for recipe curation. Developed a reproducible ranked feed and SQL-based ingredient matching, with CI gating on RuboCop, Brakeman, Semgrep, and RSpec.