Hello, I'm
Shaun Alonzo
I help engineering teams modernize legacy .NET systems, design cloud-native architectures on AWS, and ship with AI-augmented workflows. 10+ years building for fintech, real estate, and marketplace platforms across APAC and Australia.
Get In Touch
How I Can Help Your Team
.NET Modernization
Move legacy .NET Framework workloads from Windows EC2 to containerized .NET on AWS without disrupting customers.
- Phased traffic routing and .NET Standard compatibility bridges
- 5+ years of technical debt eliminated with zero customer impact
Outcome: safer releases, clearer ownership, and a platform ready for modern AWS operations.
AWS Architecture & Cloud-Native Design
Design event-driven, serverless, and containerized AWS systems that match the team’s operating model.
- SQS/SNS, EventBridge, Lambda, API Gateway, ECS Fargate, EKS, and AWS CDK
- AWS Solutions Architect Associate certified
Outcome: cloud architecture that is observable, resilient, and easier to change.
AI-Augmented Engineering
Help teams use Claude Code and GitHub Copilot responsibly across architecture, coding, tests, and reviews.
- AI practices established across architecture, code generation, and automated testing
- Best practices later adopted by multiple squads at Domain
Outcome: faster delivery loops with clearer guardrails for quality and maintainability.
Fractional Senior/Principal Engineer
Add senior .NET/AWS judgment to a critical project without waiting for a full-time hire.
- Remote delivery across APAC, Australia, UK, and US time zones
- Architecture leadership, mentoring, implementation, and delivery support
Outcome: a critical project gets senior ownership while your team keeps moving.
Skills
System design, .NET modernization, and AI-augmented engineering, supported by cloud, backend, data, and frontend skills.
Signature capabilities
The areas where I bring the most senior-level ownership to modernization and delivery work.
Backend
Build .NET services and APIs, from application architecture to data access.
Also used
Cloud & delivery
Deploy applications and connect services using AWS and Azure.
Also used
Data & caching
Store, query, and cache application data.
AI-augmented engineering
Integrate AI tools into architecture, coding, testing, and code review.
Also used
DevOps, testing & observability
Automate deployments, test user journeys, and diagnose production issues.
Also used
Frontend
Build web and mobile interfaces backed by .NET services.
Work Experience
- Led zero-downtime modernization of mission-critical services from .NET Framework on AWS EC2 (Windows) to containerized .NET on AWS EKS, eliminating 5+ years of technical debt with zero customer impact.
- Architected an event-driven Order Orchestration Engine using AWS EventBridge, SNS, and SQS to automate Salesforce order ingestion — eliminating manual steps from the sales pipeline and accelerating order processing.
- Built a reusable .NET HTTP resilience library with IHttpClientFactory, automated OAuth2 token lifecycle, and configurable circuit breakers/retries — adopted across multiple squads.
- Integrated Claude Code & GitHub Copilot into the full SDLC (architecture, coding, test generation, code review), measurably increasing team throughput sprint-over-sprint. Established AI tooling best practices later adopted across the organization.
- Migrated legacy React/.NET Framework internal tools to Retool (no-code), freeing engineering capacity from internal CRUD maintenance to focus on core revenue-generating products.
- Introduced end-to-end automated testing with Playwright in the build pipeline, validating critical frontend and backend user journeys on every deployment.
- Engineered a standardized Server-Driven UI (SDUI) framework for Editorial and Reviews pages, establishing a unified contract across Web, iOS, and Android — decoupling cross-team dependencies and reducing time-to-market.
- Decomposed a monolithic Editorial API into separate read/write paths with Redis distributed caching (CQRS), improving scalability for consuming teams.
- Led the Redbook.com.au frontend rewrite in React/TypeScript, driving a 20% traffic increase to inquiry pages.
- Shipped "Can't Find Your Car" feature end-to-end, generating 200+ new ad listings within 90 days of launch.
- Designed SOC2-compliant public APIs with ASP.NET Core and OAuth2/JWT for third-party loan submissions in a regulated fintech environment.
- Built .NET Framework ASP.NET MVC applications for loan product landing pages with responsive Razor views and form submission pipelines.
- Led the MoneyMe+ WooCommerce plugin team; integration brought in 1,000+ e-commerce leads within its first 60 days.
- Led a cross-functional squad of 10 with full ownership of sprint grooming, technical specs, weekly releases, and on-call rotation.
- Optimized lender API integration layer, reducing response times from 8s to 2s on a platform processing 150,000 transactions per day.
Earlier: BlastAsia (Software Engineer I → Dev Lead, 2016-2019) · Accenture (Associate SE, 2015-2016)
Featured Projects
Card Guide PH
A comprehensive guide for credit card information and tracking in the Philippines. AI agents (LLM + Playwright) for automated data extraction, React/Node.js on Vercel, PostgreSQL.
Redbook Website Redesign
Led the transition of Redbook.com.au from a 2000s aesthetic to a modern design, revitalizing website appearance while maintaining existing customers and boosting website views.
MoneyMe+ WooCommerce Plugin
Developed an e-commerce plugin that generated over 1000 leads within first 2 months of launch, connecting sellers with financing options.
Get In Touch
I work with engineering teams — whether that's a 3-month .NET modernization sprint, AWS architecture consulting, embedding as a fractional senior engineer, or a full-time role on a mission-driven team.
Based in the Philippines (UTC+8), working remotely with teams in Australia, the UK, and the US.