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I'm a Senior Full Stack Developer with 9 years of experience building mobile, web, backend, and cloud-native systems for membership, payment, and customer engagement platforms. I specialise in React Native, React, TypeScript, Node.js, AWS, real-time data synchronization, third-party API integrations, secure billing workflows, and legacy system modernization. I enjoy collaborating with product, QA, and stakeholder teams to design scalable solutions, migrate legacy features, and deliver high-impact features across mobile and web. I thrive in Agile environments and continually improve automation, testing, and reliability.…I'm a Senior Full Stack Developer with 9 years of experience building mobile, web, backend, and cloud-native systems for membership, payment, and customer engagement platforms. I specialise in React Native, React, TypeScript, Node.js, AWS, real-time data synchronization, third-party API integrations, secure billing workflows, and legacy system modernization. I enjoy collaborating with product, QA, and stakeholder teams to design scalable solutions, migrate legacy features, and deliver high-impact features across mobile and web. I thrive in Agile environments and continually improve automation, testing, and reliability.

Leon Roy

Full Stack Developer, Web Developer, Front-End Developer, +4

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I'm a Senior Full Stack Developer with 9 years of experience building mobile, web, backend, and cloud-native systems for membership, payment, and customer engagement platforms. I specialise in React Native, React, TypeScript, Node.js, AWS, real-time data synchronization, third-party API integrations, secure billing workflows, and legacy system modernization. I enjoy collaborating with product, QA, and stakeholder teams to design scalable solutions, migrate legacy features, and deliver high-impact features across mobile and web. I thrive in Agile environments and continually improve automation, testing, and reliability.…I'm a Senior Full Stack Developer with 9 years of experience building mobile, web, backend, and cloud-native systems for membership, payment, and customer engagement platforms. I specialise in React Native, React, TypeScript, Node.js, AWS, real-time data synchronization, third-party API integrations, secure billing workflows, and legacy system modernization. I enjoy collaborating with product, QA, and stakeholder teams to design scalable solutions, migrate legacy features, and deliver high-impact features across mobile and web. I thrive in Agile environments and continually improve automation, testing, and reliability.

Available to hire

I’m a Senior Full Stack Developer with 9 years of experience building mobile, web, backend, and cloud-native systems for membership, payment, and customer engagement platforms. I specialise in React Native, React, TypeScript, Node.js, AWS, real-time data synchronization, third-party API integrations, secure billing workflows, and legacy system modernization.

I enjoy collaborating with product, QA, and stakeholder teams to design scalable solutions, migrate legacy features, and deliver high-impact features across mobile and web. I thrive in Agile environments and continually improve automation, testing, and reliability.

Skills

Experience Level

Expert

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Language

English

Fluent

Work Experience

Senior Full Stack Developer at Fluz

January 1, 2023 - Present

Architect and build cross-platform React Native and React features for a rewards, payments, and member engagement platform; develop scalable Node.js and TypeScript backend services supporting wallet activity and real-time status updates; build admin tools; integrate third-party APIs, Stripe payments, and subscription workflows; implement push notifications and in-app messaging; lead legacy feature migrations to modern React and Node.js services while preserving data and coordinating rollout with QA, product, and stakeholders.

Senior Full Stack Engineer at Fluz

January 1, 2023 - Present

Partnered with growth, lifecycle, and analytics stakeholders to design and launch acquisition campaigns; translated campaign briefs into reusable landing page systems, API integrations, and automated reporting workflows. Built Python, JavaScript, and SQL tooling to generate segmented campaign audiences, trigger personalized outreach, and sync engagement data across HubSpot, Salesforce, Segment, and internal analytics layers. Developed an AI-assisted creative testing workflow with LLM prompts and brand guardrails to generate ad copy, email variants, and landing page messaging, reducing campaign setup time by 45%. Implemented event-driven automations for web forms, referral flows, lifecycle emails, and paid campaign attribution, improving data consistency across channels and dashboards. Designed BigQuery-based reporting models for CAC, conversion rates, campaign ROI, funnel velocity, and pipeline generation, enabling daily visibility into experiment outcomes and revenue contribution.

Senior Software Engineer at Fluz

February 1, 2022 - Present

Delivered responsive web interfaces using React and TypeScript with strong attention to layout accuracy and design fidelity. Built and maintained frontend components aligned with design specifications, ensuring consistent UI behavior across devices. Implemented SEO-friendly structures including semantic HTML, metadata optimization, and performance improvements for discoverability. Worked with dynamic and user-facing content systems, ensuring clean rendering and maintainability across different content formats. Collaborated with design and product teams to iterate quickly while preserving visual and functional quality.

Full Stack Developer at Elevance Health

March 1, 2020 - January 1, 2023

Built full-stack JavaScript and Python applications supporting digital engagement programs, segmentation workflows, operational dashboards, and data exchange between web experiences, CRM systems, and analytics platforms. Developed REST APIs, webhook handlers, and scheduled jobs to enrich audience records, route submissions, and automate lifecycle communications across internal systems and third-party tools. Wrote advanced SQL queries and data validation checks for campaign reporting and attribution, reducing manual reconciliation work for analytics and operations teams. Collaborated with business, marketing, and compliance stakeholders to translate campaign requirements into testable user stories, technical designs, QA handoffs, and release plans for high-traffic initiatives. Standardized tracking events, UTM conventions, dashboard definitions, and regression checks to improve experimentation reliability and data cleanliness.

Senior Software Engineer at Elevance Health

March 1, 2019 - January 31, 2022

Developed and maintained web applications using modern JavaScript frameworks with focus on usability and accessibility. Translated design mockups into production-ready UI with high attention to detail and cross-browser compatibility. Improved frontend performance and page load times through optimized asset handling and efficient rendering strategies. Partnered with cross-functional teams to deliver user-facing features within defined timelines and quality expectations.

Software Developer at ThoughtWorks

May 1, 2017 - March 1, 2020

Delivered custom web applications and internal tools using JavaScript, React, Node.js, Python, and SQL for clients needing scalable workflows, reporting interfaces, and heavy integrations. Built API integrations and data pipelines connecting customer, campaign, and transaction data across SaaS platforms to enable clean segmentation, automated workflows, and faster decision-making. Created reusable landing page components, forms, and analytics instrumentation to improve development speed while maintaining accessibility and performance. Supported A/B testing and personalization by implementing event tracking, experiment flags, dashboards, and QA processes for validation before rollout.

Full Stack Developer at ThoughtWorks

January 1, 2017 - February 28, 2019

Built full-stack web applications with emphasis on clean UI implementation and maintainable frontend architecture. Worked in agile delivery environments to meet tight deadlines while maintaining code quality and consistency.