Available to hire
I’m Subin Sebastian, a 15-year veteran full-stack software engineer focused on designing, building, and maintaining secure, enterprise-grade applications. I specialize in React (Hooks), TypeScript, AWS Amplify, GraphQL, and DynamoDB, alongside .NET 6 / C# microservices, CI/CD, and automated testing. I’m currently pursuing a Master’s in Cyber Security at UNSW and love turning complex business requirements into robust, high-performance solutions while upholding code quality and security in regulated environments.
I’m an effective collaborator who works closely with analysts, architects, and stakeholders to deliver reliable, user-centered digital services. I have a track record of modernising legacy codebases, delivering features end-to-end, and championing secure coding practices across distributed systems.
Skills
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Language
English
Fluent
Work Experience
Senior Developer (Security & Enterprise Systems) at Flight Centre Travel Group
January 1, 2023 - October 30, 2025Led security assessment & hardening of Airlink, ensuring PCI compliance for high-throughput invoicing. Developed secure APIs with encryption, authentication, and RBAC. Automated fraud detection workflows, reducing manual checks by 40%. Enhanced posting reversal logic with validation, audit trails, and safeguards. Integrated Airlink with payment gateways, ensuring secure data transmission.
Senior Business Application Programmer at Lockheed Martin Australia
December 1, 2022 - December 1, 2022Migrated legacy defence applications into secure bespoke solutions. Developed scalable UI modules and optimised SQL performance. Collaborated with analysts to meet military-grade security standards. Developed and deployed custom C# plugins to extend Dynamics 365 Finance and configured process workflows.
Software Developer at GP Network Pty Ltd
August 1, 2014 - August 1, 2014Built and maintained an international lottery e-commerce platform. Improved SQL performance and implemented role-based security.
Developer (B2B/B2C Web Solutions) at Allianz
December 1, 2022 - December 1, 2022Developed portals for roadside assistance and travel insurance. Optimised front-end performance and ensured secure API integrations.
Developer (GIS Solutions) at Department of Employment, Economic Development & Innovation
January 1, 2011 - January 1, 2011Built GIS-based fire ant eradication system integrating ESRI with .NET. Collaborated with analysts to ensure scalability and accuracy.
Developer (GIS Vehicle Tracking) at Queensland Rail
January 1, 2011 - January 1, 2011Delivered GPS-enabled vehicle tracking solution with real-time alerts. Maintained user roles and system security.
Analyst Programmer at Data#3 Ltd
January 1, 2010 - January 1, 2010Developed WCF-enabled applications improving performance & scalability. Implemented secure communication channels with MSMQ and authentication.
Various Roles at Early Career
January 1, 2008 - January 1, 2008Software development & leadership roles in finance, retail, and government. Worked with ASP, VB, SQL Server, Oracle, and GIS solutions.
Senior Developer (Security & Enterprise Systems) at Flight Centre Travel Group
January 1, 2023 - November 3, 2025Lead developer for Airlink and Oasis enterprise platforms supporting global travel and finance operations. Maintained and enhanced React + TypeScript front-end applications with advanced forms, data grids, and admin workflows. Integrated AWS Amplify (DataStore + GraphQL) with secure authentication and synchronised data persistence. Designed and optimised NoSQL schemas in DynamoDB; implemented event-driven logic via AWS Lambda. Delivered robust error-handling, validation, and user-feedback mechanisms improving usability and reliability. Applied modern CI/CD pipelines with automated build, test, and deployment processes in GitHub Actions. Championed code-review discipline and documentation in line with enterprise and PCI-compliance standards. Collaborated with enterprise architects to analyse and implement technical solutions across distributed systems.
Developer (GIS Solutions) at Department of Employment, Economic Development & Innovation
January 1, 2011 - November 3, 2025Built GIS-based fire ant eradication system integrating ESRI with .NET. Collaborated with analysts to ensure scalability and accuracy.
Software development & leadership roles at Early Career
January 1, 2008 - January 1, 2008Software development & leadership roles across finance, retail, and government; worked with ASP, VB, SQL Server, Oracle, and GIS solutions.
Education
Master’s in Cyber Security at University of New South Wales
January 11, 2030 - October 30, 2025Bachelor of Engineering at Mumbai University
January 11, 2030 - October 30, 2025Master’s in Cyber Security (In Progress) at University of New South Wales
January 11, 2030 - November 3, 2025Bachelor of Engineering at Mumbai University
January 11, 2030 - November 3, 2025Qualifications
NV1 Defence Clearance
January 11, 2030 - October 30, 2025Industry Experience
Government, Financial Services, Travel & Hospitality, Professional Services, Software & Internet, Computers & Electronics
Skills
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