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Senior software engineer specialising in full-stack web and mobile development, cloud-hosted backend systems, and data visualisation. I’ve led independent feature work and architectural improvements in small teams and multi-team environments, balancing product needs with reliability, performance, and maintainability. I build and scale services on AWS and other cloud platforms using Node.js (including NestJS) and React/React Native/Expo, with strong emphasis on API design, testing, database performance, internationalisation, and delivering usable UI/UX patterns—often acting as the technical owner with minimal oversight.…Senior software engineer specialising in full-stack web and mobile development, cloud-hosted backend systems, and data visualisation. I’ve led independent feature work and architectural improvements in small teams and multi-team environments, balancing product needs with reliability, performance, and maintainability. I build and scale services on AWS and other cloud platforms using Node.js (including NestJS) and React/React Native/Expo, with strong emphasis on API design, testing, database performance, internationalisation, and delivering usable UI/UX patterns—often acting as the technical owner with minimal oversight.

Mitchell Warr

Web Developer, Programmer, Back-End Developer, +2

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Senior software engineer specialising in full-stack web and mobile development, cloud-hosted backend systems, and data visualisation. I’ve led independent feature work and architectural improvements in small teams and multi-team environments, balancing product needs with reliability, performance, and maintainability. I build and scale services on AWS and other cloud platforms using Node.js (including NestJS) and React/React Native/Expo, with strong emphasis on API design, testing, database performance, internationalisation, and delivering usable UI/UX patterns—often acting as the technical owner with minimal oversight.…Senior software engineer specialising in full-stack web and mobile development, cloud-hosted backend systems, and data visualisation. I’ve led independent feature work and architectural improvements in small teams and multi-team environments, balancing product needs with reliability, performance, and maintainability. I build and scale services on AWS and other cloud platforms using Node.js (including NestJS) and React/React Native/Expo, with strong emphasis on API design, testing, database performance, internationalisation, and delivering usable UI/UX patterns—often acting as the technical owner with minimal oversight.

Available to hire

Senior software engineer specialising in full-stack web and mobile development, cloud-hosted backend systems, and data visualisation. I’ve led independent feature work and architectural improvements in small teams and multi-team environments, balancing product needs with reliability, performance, and maintainability.

I build and scale services on AWS and other cloud platforms using Node.js (including NestJS) and React/React Native/Expo, with strong emphasis on API design, testing, database performance, internationalisation, and delivering usable UI/UX patterns—often acting as the technical owner with minimal oversight.

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Intermediate

Beginner

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Work Experience

Senior Software Engineer at Tether Ltd

January 1, 2024 - January 1, 2026

Architected, scoped, and built an AWS-hosted background jobs management system using BullMQ and Valkey. Modernised and maintained an Expo React Native app across multiple versions, including diagnosing and rebuilding a push notification system. Built interactive multi-dimensional data visualisations and graphs using D3-style approaches and performance-focused frontend techniques. Guided correct application-wide timezone and daylight savings calculations. Worked in a small team of three senior developers operating in isolation, delivering features as vertical slices: defining solution approach from problem statements; designing new APIs and validations; updating microservice permissions and SDK interfaces; performing database schema changes and migrations; adding unit test coverage; implementing React UI following established patterns; and communicating design/impact through standups and PR reviews.

Senior Software Engineer at Fingermark Ltd

January 1, 2023 - January 1, 2024

Worked across multiple teams and domains to design and integrate full-stack products with existing systems. Helped design and implement a new microservice architecture focused on scalability and reducing maintenance costs; reused the architecture to lead delivery of a NestJS customer loyalty service integrating multiple providers/APIs. Led technical-debt prioritisation with product and engineering stakeholders across a team of 20+ engineers, improving security risk handling, error tracking, and migrations from older platform versions. Took ownership of a long-standing Verifone eftpos integration and drove it from a failing state to full certification over two months. Designed and rolled out a product integrating multiple Point-of-Sale systems (NestJS service + React app with multiple customer skins). Led a React codebase migration approach to support multiple teams working on shared code with minimal regressions and customisation goals, and re-architected the deployment flow to remove

Intermediate Software Engineer at AskYourTeam

January 1, 2018 - January 1, 2023

Contributed to a migration from a Ruby on Rails monolith to a distributed monolith architecture with React on the frontend. Responsible for health and devops of the React codebase and its dependencies. Partnered with product/design to define and build new UI/UX flows and components. Led performance refactoring for reporting by rewriting Rails code and SQL to reduce a heatmap query from ~90 seconds at peak load to under 2 seconds, while adding pagination of aggregated rows (other queries reduced from ~30 seconds to ~200ms). Created a D3 reporting suite fully customised to design requirements, integrating D3 primitives into a declarative React pattern with animation and performance optimisations. Built a heatmap chart with virtualised scrolling and an overlay minimap that remained a top offering due to usability/performance and strong customer feedback. Seconded to a 6-person internal team to complete a 1-month Rails/SQL migration transforming a jsonb key/value structure into a key arra

Software Developer / Frontend AngularJS / Mobile (Swift) / Golang at WeaveIT

January 1, 2016 - January 1, 2018

Early-career developer with junior-level experience across multiple project types with limited oversight. Delivered quick enterprise solutions from design to release, including frontend work with AngularJS, mobile development for Android/iOS using Swift, and backend development using Golang.

Software Developer at WeaveIT

January 1, 2016 - January 1, 2018

Delivered small enterprise solutions from design to release with junior-level support and limited oversight. Worked across multiple platforms/projects including frontend development with AngularJS, mobile development (Android and iOS using Swift), and backend development in Go.