Looks like you have JavaScript disabled. For the full Twine experience, you will need to re-enable it.

I'm John Tapsell, a versatile senior software engineer with a passion for building scalable web apps and modern architectures. I enjoy guiding teams, mentoring juniors, and shipping features that customers love. My experience spans full-stack development, cloud infrastructure, API design, and developer tooling across fintech, media, and ecommerce domains. In my free time I contribute to open-source projects, explore new technologies like AI tooling, and strive to improve development processes through automation and best practices.…I'm John Tapsell, a versatile senior software engineer with a passion for building scalable web apps and modern architectures. I enjoy guiding teams, mentoring juniors, and shipping features that customers love. My experience spans full-stack development, cloud infrastructure, API design, and developer tooling across fintech, media, and ecommerce domains. In my free time I contribute to open-source projects, explore new technologies like AI tooling, and strive to improve development processes through automation and best practices.

John Tapsell

Full Stack Developer, Web Developer, Back-End Developer, +2





I'm John Tapsell, a versatile senior software engineer with a passion for building scalable web apps and modern architectures. I enjoy guiding teams, mentoring juniors, and shipping features that customers love. My experience spans full-stack development, cloud infrastructure, API design, and developer tooling across fintech, media, and ecommerce domains. In my free time I contribute to open-source projects, explore new technologies like AI tooling, and strive to improve development processes through automation and best practices.…I'm John Tapsell, a versatile senior software engineer with a passion for building scalable web apps and modern architectures. I enjoy guiding teams, mentoring juniors, and shipping features that customers love. My experience spans full-stack development, cloud infrastructure, API design, and developer tooling across fintech, media, and ecommerce domains. In my free time I contribute to open-source projects, explore new technologies like AI tooling, and strive to improve development processes through automation and best practices.

Available to hire

I’m John Tapsell, a versatile senior software engineer with a passion for building scalable web apps and modern architectures. I enjoy guiding teams, mentoring juniors, and shipping features that customers love. My experience spans full-stack development, cloud infrastructure, API design, and developer tooling across fintech, media, and ecommerce domains.

In my free time I contribute to open-source projects, explore new technologies like AI tooling, and strive to improve development processes through automation and best practices.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

English

Fluent

Work Experience

Senior Software Engineer at Fiserv

August 1, 2024 - November 27, 2025

Led the design and implementation of a headless CMS and SDK used by internal and external teams. Drove feature discovery for image upload optimization and document versioning capabilities. Architected and implemented a Strangler pattern migration using a reverse proxy to enable incremental modernization with zero downtime for global users. Mentored junior developers, supported onboarding, and contributed to technical growth across a small, cross-functional team. Built secure OAuth flows for bank connections and integrated AWS services to support scalable, resilient web applications.

Online Contractor at NZME

January 1, 2022 - January 1, 2022

Contracted to build and maintain full-stack web features for client-facing and internal products. Tech stack included TypeScript with React, Node.js, DynamoDB, and Redis. Created API endpoints and frontend components, and integrated third-party tools such as Optimizely and Salesforce. Worked across multiple applications, collaborating with internal teams to deliver robust, scalable solutions.

Full Stack Web Developer at Moustache Republic

November 1, 2020 - November 1, 2020

Full-stack web developer focusing on ecommerce development. Worked in an agile team delivering high-quality sites using BigCommerce and Shopify, including theme customization and integration tasks. Tech stack included AWS, JavaScript and Python; collaborated with clients to define scope, and supported data integrations from third-party services (e.g., SAP and ERP systems). Led initiatives to improve reliability and performance and mentored junior developers.