PROFESSIONAL PROFILE — Tirelo David Oabile Source: https://david.sigmar.au/profile.txt · Updated: 2026-10-08 Name: Tirelo David Oabile Preferred name: David Professional roles: Principal Software Engineer Software Architect Solution Architect Engagement: Contract / Consulting Available: Immediately Location: Flexible on location Citizenship: Australian Government: Eligible to obtain Australian Government security clearance Experience: 17+ years Primary capabilities: Software architecture Distributed systems Cloud architecture Enterprise integration API architecture Platform modernisation Secure systems Event-driven architecture PaaS and SaaS integration Selected scale: 140+ retail stores ~14,000 SKUs per store Millions of API requests per day >99.9% availability <120 ms P95 latency Education: Master of Finance and Banking Bachelor of Information Technology Contact: Email: my-career@sigmar.io LinkedIn: https://www.linkedin.com/in/tirelo-oabile-00b8ba20/ SUMMARY Principal-level hands-on engineer and software architect with 17+ years of experience designing, modernising and operating business-critical systems across retail, eCommerce, POS, healthcare, finance, cloud and data platforms. Strong background in secure API and integration architecture, distributed and event-driven systems, cloud infrastructure, data protection, platform modernisation and production reliability. Experienced in regulated environments and in translating operational requirements into maintainable, auditable technical solutions. Comfortable operating as an individual contributor, technical lead or architecture authority. ENGAGEMENT Types: Contract, Consulting Available: Immediately Location: Flexible on location Target engagements: - Australian Government and government-adjacent technology contracts - Principal / Senior Software Engineer - Software / Solution Architect - Technical Lead - Integration / Platform Modernisation Private sector: Also open to private-sector contract and consulting engagements where hands-on architecture, modernisation, integration or complex software delivery is required. Government: Eligible to obtain Australian Government security clearance; available to pursue roles requiring that eligibility. SELECTED SCALE AND OUTCOMES - 140+ retail stores — Nutrition Warehouse — architecture spanning POS, eCommerce, inventory and integrations. - ~14,000 SKUs per store — Nutrition Warehouse — across 140+ retail locations. - Millions of API requests per day — Nutrition Warehouse — designed for scale, latency isolation and high-traffic production operation. - >99.9% availability — Nutrition Warehouse — order and inventory services maintained through peak trading periods. - <120 ms P95 latency — Nutrition Warehouse — core API P95 latency. - ~60–70% fewer failure incidents — Nutrition Warehouse — reduced synchronous dependencies using event-driven processing. INDUSTRIES - Retail - eCommerce - POS - Healthcare - Finance - Cloud and data platforms CORE CAPABILITIES - Solution & software architecture - Secure API & integration architecture - Platform modernisation & legacy migration - Cloud architecture: AWS & Azure - Identity, access control & data protection - Event-driven & distributed systems - Relational & non-relational data design - Reliability, performance & cost optimisation - CI/CD, Linux & production operations - Technical leadership & engineering standards - Agile/Scrum delivery & stakeholder collaboration - AI-assisted engineering & data workflows TECHNOLOGIES Languages: TypeScript / JavaScript, Node.js, Go, Python, PHP, Rust, C#, SQL Cloud & Infrastructure: AWS Lambda, API Gateway, EC2, SQS, VPC, IAM, Azure, Cloudflare Workers/Queues, Docker, Kubernetes, Linux Data & Messaging: PostgreSQL, SQL Server / MSSQL, MySQL, MongoDB, Redis, Kafka Architecture & Delivery: REST, GraphQL, Event-driven architecture, Serverless, Distributed systems, CI/CD, Git, Agile/Scrum Security: Encryption at rest/in transit, RBAC/access control, Auditability, Data boundaries, API security, OWASP-oriented hardening EXPERIENCE Nutrition Warehouse Title: Software Architect / Principal Engineer Period: Nov 2016 – Present Basis: Part-time, 4 days/week Industry: Retail & eCommerce Page: https://david.sigmar.au/experience/nutrition-warehouse Highlights: - Architecture owner for eCommerce, POS, inventory and integration platforms supporting 140+ retail locations and approximately 14,000 SKUs per store. - Designed and implemented REST and GraphQL APIs for order fulfilment, inventory management, POS reconciliation and third-party integrations. - Architected systems handling millions of daily API requests; reduced core API P95 latency to below 120 ms and maintained >99.9% availability for critical order and inventory workflows. - Reduced failure-related incidents by approximately 60–70% by decoupling webhooks, stock updates and POS events with AWS SQS and asynchronous processing. - Built high-throughput inventory synchronisation services and introduced failure-aware patterns including request isolation, backpressure and graceful degradation. - Delivered headless and serverless architectures across AWS, Cloudflare, Vercel, Contentful and Shopify while modernising legacy Magento integrations without service disruption. - Defined API contracts, integration standards and engineering approaches; collaborated with product and operations in Agile/Scrum delivery. Technologies: REST, GraphQL, AWS, AWS SQS, Cloudflare, Vercel, Contentful, Shopify, Magento FordHealth Pty Ltd Title: Software Architect & Systems Engineer Period: 2024 – 2025 Industry: Healthcare Page: https://david.sigmar.au/experience/fordhealth Highlights: - Owned architecture for a greenfield healthcare platform with responsibility for sensitive-data protection, system migration and compliance-oriented design. - Integrated application services with Azure authentication and SharePoint-based patient records, including secure document upload and retrieval workflows. - Designed encryption models for sensitive healthcare information at rest and in transit, with strict access control, auditability and data-boundary enforcement. - Led migration and redesign work across C#/PHP and SQL-based systems, improving maintainability and deployment simplicity. Technologies: Azure authentication, SharePoint, C#, PHP, SQL Sigmar Pty Ltd Title: Software Architect & Systems Engineer Period: 2022 – 2025 Basis: Part-time Industry: Finance & platform development Page: https://david.sigmar.au/experience/sigmar Highlights: - Designed greenfield financial, data-intensive and distributed systems, including backend APIs on hardened Linux environments. - Developed PostgreSQL extensions in Rust and financial/analytical pipelines using Python and Rust. - Implemented Kafka-based high-throughput messaging, structured logging and monitoring, cryptographic signing using SHA-256/ED25519 and Protocol Buffers. - Built security-sensitive platform capabilities including encrypted customer data, wallets, tokens and private-ledger components. Technologies: Linux, PostgreSQL, Rust, Python, Kafka, SHA-256, Ed25519, Protocol Buffers Skin02 Pty Ltd Title: Software Architect & Integration Engineer Period: 2021–2022, 2025 Basis: Contract, 6 months total Industry: Beauty & skincare eCommerce Page: https://david.sigmar.au/experience/skin02 Highlights: - Integrated Shopify with MYOB Exo across orders, customers, products and stock. - Designed reliable synchronisation pipelines using MongoDB and Node.js services, with SQL Server/MSSQL optimisation to reduce database load. Technologies: Shopify, MYOB Exo, MongoDB, Node.js, SQL Server / MSSQL Follow Agency Title: Senior Web Developer / Technical Lead Period: Jan 2015 – Dec 2015 Industry: Digital agency (eCommerce) Page: https://david.sigmar.au/experience/follow-agency Highlights: - Delivered Magento architecture, custom integrations and security hardening for medium-to-large eCommerce deployments. - Led and reviewed offshore engineering work; performed OWASP-oriented security reviews and server hardening; contributed to Android/iOS system architecture. Technologies: Magento, OWASP, Android, iOS PRODUCT AND ENGINEERING WORK - Profit Guard / HTQL: Designed and built a financial intelligence platform for Shopify merchants and its domain-specific financial/eCommerce query engine, with emphasis on correctness, auditability, analytics and extensibility. - Sigmar AOS: A privacy-first platform to coordinate people, organisations and real-world operations through deterministic, auditable workflows, built on the Sigmar Finance Protocol. In development. - AI-assisted engineering: Uses structured AI-assisted workflows for analysis, specification and engineering productivity while retaining explicit architectural, security and testing controls. EDUCATION - Master of Finance and Banking — Edith Cowan University - Bachelor of Information Technology — Central Queensland University CERTIFICATIONS - Certificate in Business Blockchain — Linux Foundation - Transaction SQL (SQL Server 2000) — New Horizons Learning Centre Referees: Available on request.