Hi, I’m Lucas Lee, a senior Ruby on Rails and Shopify developer based in Singapore with 8+ years of experience building scalable web apps, Shopify themes, and custom apps. I combine strong backend architecture with modern frontend skills to deliver high-performing ecommerce and SaaS platforms, optimizing performance, reliability, and developer productivity. I enjoy turning complex problems into clean, maintainable code and collaborating with product and design teams to ship features that drive growth. When I’m not coding, I’m exploring AI-driven interactions, performance optimizations, and new tech to keep merchants competitive and users engaged.…

Lucas Lee

PRO

Hi, I’m Lucas Lee, a senior Ruby on Rails and Shopify developer based in Singapore with 8+ years of experience building scalable web apps, Shopify themes, and custom apps. I combine strong backend architecture with modern frontend skills to deliver high-performing ecommerce and SaaS platforms, optimizing performance, reliability, and developer productivity. I enjoy turning complex problems into clean, maintainable code and collaborating with product and design teams to ship features that drive growth. When I’m not coding, I’m exploring AI-driven interactions, performance optimizations, and new tech to keep merchants competitive and users engaged.…

Available to hire

Hi, I’m Lucas Lee, a senior Ruby on Rails and Shopify developer based in Singapore with 8+ years of experience building scalable web apps, Shopify themes, and custom apps. I combine strong backend architecture with modern frontend skills to deliver high-performing ecommerce and SaaS platforms, optimizing performance, reliability, and developer productivity.

I enjoy turning complex problems into clean, maintainable code and collaborating with product and design teams to ship features that drive growth. When I’m not coding, I’m exploring AI-driven interactions, performance optimizations, and new tech to keep merchants competitive and users engaged.

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Skills

Experience Level

Ruby on Rails
Expert
Ruby
Expert
AWS
Expert
Shopify
Expert
Docker
Expert
PostgreSQL
Expert
Node.js
Expert
Redis
Expert
GraphQL
Expert
MySQL
Expert
React JS
Expert
React Native
Expert
TypeScript
Expert
Kubernetes
Expert
Express
Expert
api
Expert
Python
Expert
Ethers.js
Intermediate
Django
Intermediate
Solidity
Intermediate
TensorFlow
Intermediate
Golang
Intermediate
Go
Intermediate
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Language

English
Fluent

Work Experience

Frontend Engineer at Freelance – Independent Projects
December 1, 2024 - Present
Led 40+ production React and Next.js applications for diverse clients. Implemented SSR/ISR and code-splitting to reduce page load times by 1.8–3.2s and boosted Lighthouse performance by 28–52%. Built 20+ reusable UI libraries with TypeScript and Tailwind, reducing future dev time by ~36%. Integrated REST and GraphQL APIs to cut client-side latency by ~25%. Developed reusable hooks and state systems, reducing bugs by ~22%. Shopify eCommerce development across 30+ stores with dynamic sections and metafield-driven CMS; optimized storefronts to achieve 85–95 Analyzer scores and a 12–34% conversion lift. Built 12+ custom Shopify apps using Rails and Node.js (subscriptions, loyalty, bundles, AI recommendations, analytics dashboards) and automated inventory/orders/integrations (20–50% workload reduction). Implemented Shopify Scripts, Functions, and checkout extensibility; integrated 20+ tools (Klaviyo, Recharge, Gorgias, ERP/POS). nopCommerce development across 8+ enterprise stores;
Senior Ruby on Rails Developer at BrainCave
December 1, 2022 - November 1, 2024
Delivered 15+ Rails applications including marketplaces, subscriptions, dashboards, and analytics systems. Improved API throughput by 45–70% using Postgres and Redis; achieved 80–92% test coverage with RSpec and FactoryBot. Built CI/CD pipelines with GitHub Actions, reducing release time by 50%. Casino betting game development: 12+ betting engines handling 2,000–5,500 concurrent users with <60ms latency; RNG and fairness verification; AI-based game balancing with 1M+ test rounds; animated casino UIs with Phaser/WebGL boosting retention by 18–25%. Blockchain and AI integrations: 4+ smart contracts for tokens, staking, and rewards; cryptographic fairness proofs; AI-driven bot behavior models; automated blockchain payout and verification tools.
Software Engineer (Full Stack) at Span.io
January 1, 2022 - November 1, 2022
Built an entire React Native installation app in 21 days for a hardware launch; integrated IoT device pairing and telemetry with 99.2% reliability. Reduced app crash rate by 28% and load time by 34%. Built real-time data pipelines using GraphQL and WebSockets; implemented authentication, offline mode, and OTA updates. Built CI/CD pipelines reducing deployment errors by 90%. Created automated hardware and UI tests, increasing regression coverage to 70%+.
Full Stack Engineer at BlueSG
April 1, 2021 - December 1, 2021
Rebuilt backend systems for rental and billing supporting 1M+ annual transactions. Designed microservices including full Rental Service lifecycle. Reduced external dependency by 63%, improving API speed by 27%. Reduced technical debt by 40% through modular refactors. Increased test coverage to 72%+. Reduced rental incidents by 35% through better monitoring.

Education

Bachelor of Computing (Honors), Computer Science at National University of Singapore
January 1, 2017 - January 1, 2021

Qualifications

Add your qualifications or awards here.

Industry Experience

Software & Internet, Retail, Media & Entertainment, Professional Services
    paper Full Stack Engineer | eCommerce Developer

    Built a high-performance eCommerce website using Next.js and modern web technologies. The platform supports a large product catalog, fast search and filtering, secure checkout, and responsive design. Focused on SEO, speed, and scalability using server-side rendering and optimized APIs. Designed to handle high traffic while delivering smooth user experience.

    Tech Stack: Next.js, React, TypeScript, Node.js, REST/GraphQL APIs, Tailwind/SCSS, Stripe/PayPal, Cloud hosting (Vercel/AWS), CI/CD.

    paper Full-Stack Developer – AI Crypto Trading Platform

    Built an end-to-end AI-based crypto trading platform, handling both frontend and backend development.

    Key Contributions:

    Developed responsive frontend using React.js for real-time trading dashboards and analytics

    Built backend services with Node.js for trade execution, data processing, and API integration

    Integrated AI models for market prediction and automated trading strategies

    Designed REST APIs for secure communication between frontend, backend, and AI services

    Implemented authentication, user management, and trade history tracking

    Optimized performance for real-time market data handling

    Tech Stack: React, Node.js, Express, REST APIs, WebSockets, AI/ML integration, Crypto APIs