Open to opportunities

Stephen Thomas

@stephenthomas1

Message

Senior full-stack engineer building scalable web apps, APIs, and cloud-native systems.

Ireland

Message

What I'm looking for

I seek senior engineering roles owning end-to-end systems, emphasizing scalable cloud-native architectures, performance, mentorship, and cross-functional impact.

I am a senior full-stack engineer with 10+ years building scalable web applications, APIs, and cloud systems across fintech, e-commerce, and agency environments. I focus on clean architecture, performance optimizations, and delivering features that improve product outcomes.

At Finastra I led backend development of Node.js and GraphQL microservices, developed microfrontends with React and Svelte, and delivered AWS-native solutions while meeting PCI compliance. I improved peak payment performance by 40%, reduced manual KYC review using LLM-based integrations, and shipped React Native mobile features with offline support.

I mentor junior engineers, introduce CI/CD and platform stability improvements, and collaborate closely with product and design to build user-focused features. I thrive in distributed teams and enjoy owning systems end-to-end to drive measurable business impact.

Experience

Work history, roles, and key accomplishments

Senior Full Stack Engineer

Finastra

Jul 2022 - Oct 2025 (3 years 3 months)

Led backend development of Node.js and GraphQL microservices supporting payments and loans, improving peak payment performance by 40% and reducing manual KYC reviews ~30% via LLM integrations. Delivered AWS-native solutions meeting PCI compliance and mentored junior engineers.

GraphQL Redis React TypeScript AWS Lambda DynamoDB React Native NodeJS

Senior Full Stack Engineer

Dept

May 2019 - Jun 2022 (3 years 1 month)

Built a multitenant e-commerce platform with React/Next.js and Django APIs, introduced tenant isolation and Stripe payments, and cut deployment time by 50% via CI/CD. Stabilized peak load with Redis rate limiting and tenant-aware caching.

React Next.js Python Django PostgreSQL Redis Stripe GitHub Actions TailwindCSS

Full Stack Engineer

Valtech

Aug 2016 - Apr 2019 (2 years 8 months)

Built analytics dashboards with Vue.js and D3 and created Flask APIs and Kafka/Kinesis pipelines to reduce dashboard latency while managing AWS infrastructure (EC2, S3, RDS) and adding SAML SSO support.

Vue.Js D3 Flask Kafka Kinesis AWS EC2 S3 RDS SAML

Full Stack Engineer

Wiredmark

Jan 2015 - Jul 2016 (1 year 6 months)

Developed marketing and automation tools using Laravel and MySQL, created reusable UI components that reduced campaign setup time by 40%, and implemented CI/CD with CircleCI and Heroku.