Harmen Dark

About

Technical lead with 13+ years of experience building and scaling high-performance distributed systems, cloud-native platforms, and full-lifecycle product delivery. Hands-on across Python, React, AWS, and AI/ML tooling, with a focus on concurrency, reliability, and engineering leadership.

Experience

• Lead Trainer & Assessor
  Institute of Data (IOD) · Auckland, NZ
  Mar 2026 – Present

  Lead technical instruction and assessment for software engineering bootcamp cohorts. Designed session content, evaluated submissions, and provided structured written feedback across fullstack, cloud, and AI modules. Mentored students through hands-on lab work spanning software development principles, frontend engineering, and cloud architecture.

• Senior Software Engineer
  Xero · Auckland, NZ
  Jun 2025 – Jun 2026

  Delivered a rebuild of Xero's primary navigation product in React and TypeScript. Architected and built an AI-powered analytics solution using Kafka, .NET, React, and AWS Bedrock. Drove accessibility enhancements, implemented feature flagging and redundancy layers, rebuilt localisation architecture, migrated SLO and observability features to IaC via Terraform, and implemented multiple AI initiatives including automated triaging, spec-driven development, and AI-assisted code reviews.

• Technical Lead (Contract)
  Joker Seven · Auckland, NZ
  Jan 2025 – Jun 2025

  Owned the full technical architecture of a greenfield mobile application. Led rapid prototyping of AI initiatives to ship the company's first production AI system end-to-end and delivered a reusable React Native component library. Engineered a CQRS layer between UI and backend, including contract development.

• Senior Software Engineer (Contract)
  Amazon · London, UK
  Jul 2024 – Dec 2024

  Rebuilt the SCP UI for an internal Amazon merchant portal. Designed the merchant workflow API layer in Java, established frontend-backend contracts, and developed a scalable RESTful API with Java, Guice, and JAX-RS for zero-downtime canary deployment.

• Technical Lead
  Machina Consulting · London, UK
  Oct 2023 – Dec 2024

  Delivered full-stack technical leadership and product ownership for Restaurant Brands and Entertainment Partners. Rolled out a new region of the platform to the North American market using Python, FastAPI, asyncio, and pytest. Integrated multiple providers into a high-throughput payment pipeline and rearchitected the pipeline to handle pre-order processing.

• Technical Lead (Contract)
  Archax · London, UK
  Nov 2022 – Oct 2023

  Built FDC3-compliant institutional trading dashboards end-to-end in Electron, WebSockets, TypeScript, and D3.js. Led product architecture discussions, worked with stakeholders on GDPR, AML, and KYC compliance, architected a zero-downtime deployment pipeline on AWS Lambda and S3, and defined event schemas and API contracts between the dashboard layer and core exchange systems.

• Technical Lead
  Machina Hero · Edinburgh, UK
  Jul 2019 – Nov 2022

  Delivered full-stack technical leadership and products for multiple clients including Nucleus Financial, Twig Education, Zonal, VisitScotland and Rackspace. Rebuilt an on-premise logistics application for Rackspace / Aramex into a cloud-native Python microservices solution, architected React products, built React Native features, implemented MFE architecture, engineered an SSR layer, and rebuilt CI/CD pipelines with automated testing and accessibility audits.

• Technical Lead (Contract)
  NZ Trade & Enterprise · Auckland, NZ
  Jul 2018 – Jun 2019

  Led architecture and delivery of a government export portal serving 5,000+ businesses. Reduced page load times through caching and UX redesign, architected a scalable backend integrating with Microsoft Dynamics and Okta SSO, defined data models and service boundaries, implemented a graph database layer, and set technical direction for syncing between systems with Azure Logic Functions.

• Senior Software Engineer (Contract)
  NZ Transport Agency · Auckland, NZ
  Nov 2017 – Jul 2018

  Delivered features across multiple mobile applications including API integrations, component libraries, and frontend tooling across a high-traffic platform. Implemented an automated testing framework and performed Scrum Master duties.

• Senior Software Engineer (Contract)
  Propellerhead · Auckland, NZ
  Feb 2017 – Nov 2017

  Built AT Mobile features including an automated testing solution to reduce manual workload and uncaught errors, and enhanced the Auckland Transport GTFS API.

Skills

Tools / apps / platforms