About

Backend engineer, AI researcher, and careful systems thinker.

The short version: I work on payment-adjacent backend systems, migrate legacy applications, do active AI research, and help teams adopt cloud and AI tooling practically.

Puvaan Raaj

I’m Puvaan Raaj, a software engineer from Malaysia. My center of gravity is backend engineering: APIs, queues, workers, observability, infrastructure, and tools that make engineering teams faster.

Right now, my work has four lanes: production backend ownership, legacy application migration, agentic AI in the cloud, and serving as Fiuu’s Claude DRI. I do active AI research alongside this — reading papers, running experiments, tracking what's moving in the field. That means I care about the code path, the rollout path, the research frontier, and whether other engineers can actually use the thing after the first demo.

The previous version of this site listed too many implementation details from company work. This rebuild turns that into a cleaner professional narrative: payment enablement, cloud modernization, platform reliability, developer productivity, and AI research.

Outside structured work hours, I'm still at it — personal AI projects, reading research papers, building small tools to stress-test ideas. Most days run 12–14 hours. The curiosity and the craft blur together. Receipt parsing teaches product privacy. A password generator becomes a post-quantum crypto lab. A paper on attention mechanisms becomes a weekend implementation.

Experience

The work story, with the useful details kept intact.

My old site had more detail, and that detail matters. This version keeps the company name, timeline, and real engineering themes, while still avoiding anything that should stay inside private implementation context.

Payment-adjacent backend systemsApple TTP-related enablementAI tool adoption and governanceCloud adoption and modernizationWorker reliability and queuesAPI design and integrationsObservability and debuggingDeveloper tooling and documentation
Jan 2024 - Present

Fiuu's Claude DRI · Agentic AI in Cloud

Software Engineer

Fiuu (Formerly Known as Razer Merchant Services)

Production backend engineer across payment platforms, merchant systems, cloud modernization, queue-driven workers, and developer productivity. In 2026, I am also Fiuu’s Claude DRI, helping move agentic AI and useful engineering practices from experiments into team habits.

2026 Key Initiatives

  • Serving as Fiuu’s Claude DRI, driving agentic AI and practical engineering adoption.
  • Supporting Apple Tap to Pay-related payment enablement and rollout work at a safe public altitude.
  • Improving backend reliability across API, worker, queue, observability, and deployment paths.
  • Turning AI-assisted engineering into documented workflows, review habits, and reusable internal tools.

2025 Payment Product Localization & Infrastructure Modernization

  • Designed and developed ISO 8583 payment server infrastructure for Virtual Terminal and Tap on Phone payment flows.
  • Migrated core payment queue processing from Gearman to RabbitMQ to improve reliability and operational clarity.
  • Supported RPP modernization work, including runtime migration, monitoring, and ECS optimization.
  • Integrated terminal payment channel support and reviewed backend application changes across payment services.

2025 Merchant Portal & API Enhancements

  • Revamped API integrations for add-on channels to improve merchant experience and integration reliability.
  • Optimized settlement and transaction listing workers for stronger data accuracy and operational confidence.
  • Led migration work for Merchant Portal services to AWS ECS to improve scalability and uptime.
  • Integrated tax calculation logic into settlement details and refactored APIs for microservices gateway readiness.

2025 Cloud, Cost Optimization & Infrastructure as Code

  • Reduced recurring infrastructure cost by offloading roughly USD 3,000 per month through cloud optimization work.
  • Applied AWS Fargate Spot where appropriate for cost-conscious compute patterns.
  • Used Terraform to provision and manage AWS resources declaratively.
  • Built reusable Terraform modules for S3, Lambda, and SQS patterns.

2025 Developer Productivity & Internal Tooling

  • Built internal tools including an ISO8583 EMV parser and utilities that shorten debugging feedback loops.
  • Set up regional sandbox environments for Malaysia and Indonesia.
  • Conducted AI-assisted code review experiments around MCP server workflows.
  • Authored API documentation and implemented PHPUnit test suites for payment applications.

2024 Merchant Onboarding Platform Improvement

  • Engineered modular architecture for Merchant Onboarding Channel Engine work.
  • Developed merchant self-service portal modules for adding channels and stores.
  • Set up regional sandbox environments for Malaysia and Indonesia markets.

2024 Merchant Portal API Suite Expansion

  • Developed and deployed backend APIs with Laravel.
  • Reduced operational cost by migrating workloads from EC2 to AWS Fargate ECS.
  • Assisted PCI-DSS remediation work through backend and infrastructure fixes.

2024 Payment Product Regionalization & Cost Optimization

  • Developed Laravel-based SNAP API support for the Indonesian market.
  • Implemented AWS cost-saving measures through lifecycle policy and storage cleanup changes.
Payment backendISO 8583RabbitMQAWS ECSTerraformLaravelAI adoptionCloud adoption
Q4 2025

Internal recognition

Unsung Hero recognition

Fiuu

Recognized for dependable technical contribution and steady ownership across backend delivery, integration work, operational cleanup, documentation, and team support.

Backend deliveryIntegration workOperational cleanupTeam support
Q4 2024

Recognition season

Rising Star recognition

Fiuu

Moved from learning the edges of a real payment environment into production engineering habits: reading logs, tracing flows, asking better questions, and building enough context to contribute safely across APIs, cloud services, and support-heavy systems.

Payment domain learningAPI and worker flowsCloud exposureProduction habits
2023

Starting point

Internship, foundations, and first real systems

Razer Merchant Services

Built the foundation through internship work, self-learning, mentors, and a lot of careful exploration. This is where backend engineering stopped being abstract and started becoming a craft.

Self-studyMentorshipSystem reading

Operating notes

Keep production boringWrite without leakingBuild small tools to learn big systemsAsk better questionsShare what is useful