Payment Platform Engineering
High-throughput backend work across queues, APIs, workers, integrations, and reliability improvements, described at the domain level instead of naming sensitive internals.
Backend engineer from Malaysia
Hello, I'm Puvaan Raaj
Puvaan is a Malaysia-based backend engineer building payment systems, cloud infrastructure, developer tools, and privacy-first AI experiments.
Now
Building backend systems around payment flows, worker reliability, APIs, and production operations without exposing private company details.
How I Learn
I turn curiosities into tools: local AI assistants, incident dashboards, OCR utilities, password/security labs, and small products that teach the real tradeoffs.
Thread
My story is mentorship, self-learning, cloud systems, careful writing, and getting better at explaining complex work in a simple public voice.
Production focus
Payments
Company awards
2
Favorite layer
Backend
Build style
Privacy-first
Work story
A clearer way to explain the experience
Cloud Modernization
Containerizing legacy workloads, moving services to managed compute, tuning CI/CD, and using infrastructure as code for repeatable environments.
Developer Tools
Small tools, parsers, dashboards, docs, and automation that shorten feedback loops for engineers and make complex systems easier to operate.
AI & Security Experiments
Privacy-first assistants, OCR workflows, post-quantum crypto demos, local LLMs, and applied research notes from building in public.
Selected work
Projects with a point of view
2026
AI Receipt Splitter
Split bills fairly in seconds with AI-powered OCR, multi-currency support, and a stateless privacy-first architecture.
AIClaude VisionGoReactPrivacy
2025
DocuLens - Image to Docx
Transform physical documents into editable Word files using OCR and AI-assisted formatting.
OCRClaudeGoogle VisionDocuments
2026
Quantum-Safe Password Generator
Generate passwords resistant to quantum computer attacks using ML-KEM, Argon2id, Go, Lambda, and WebAssembly.
SecurityGoAWS LambdaWASM
Ghostwrite
2026
Ghostwrite
A Go CLI tool that tracks and attributes AI-generated code in git repositories.
GoGitAIDeveloper ToolsCLI
Personal Assistant RAG
2026
Personal Assistant RAG
A production-grade AI personal assistant using Go, Next.js, Qdrant, AWS S3, Docker, and retrieval-augmented generation.
GoNext.jsRAGQdrantAWS S3DockerAI
Confidential AI Gateway
2026
Confidential AI Gateway
Zero-trust serverless gateway that strips PII before requests reach public AI providers.
GoAWS LambdaKMSNitro EnclavesAISecurity
2026
AI Receipt Splitter
Split bills fairly in seconds with AI-powered OCR, multi-currency support, and a stateless privacy-first architecture.
AIClaude VisionGoReactPrivacy
2025
DocuLens - Image to Docx
Transform physical documents into editable Word files using OCR and AI-assisted formatting.
OCRClaudeGoogle VisionDocuments
2026
Quantum-Safe Password Generator
Generate passwords resistant to quantum computer attacks using ML-KEM, Argon2id, Go, Lambda, and WebAssembly.
SecurityGoAWS LambdaWASM
Ghostwrite
2026
Ghostwrite
A Go CLI tool that tracks and attributes AI-generated code in git repositories.
GoGitAIDeveloper ToolsCLI
Personal Assistant RAG
2026
Personal Assistant RAG
A production-grade AI personal assistant using Go, Next.js, Qdrant, AWS S3, Docker, and retrieval-augmented generation.
GoNext.jsRAGQdrantAWS S3DockerAI
Confidential AI Gateway
2026
Confidential AI Gateway
Zero-trust serverless gateway that strips PII before requests reach public AI providers.
GoAWS LambdaKMSNitro EnclavesAISecurity
Personal operating system
Writing, research, talks, reading, watching
Notebook
Writing & Research
Medium posts, local notes, applied research, and talk drafts in one place.
Research
AI-Assisted Operations Without Losing Control
AI systems
Talks
Private AI Code Review Loops
Draft workshop
Books
Designing Data-Intensive Applications
Martin Kleppmann
Movies
Dune: Part Two
Denis Villeneuve
Writing
Recent notes
Apr 18, 2026
Building a Persistent Knowledge Base for Claude Code: From Session Amnesia to Compounding Intelligence
A long-form engineering deep-dive into applying Karpathy's LLM-wiki pattern to Claude Code: transcript-replay auto-updates, Obsidian as source of truth, the honest trade-offs of Graphiti and custom builds, and a full survey of where else a personal knowledge base can live in 2026.
Jan 27, 2026
AI Receipt Splitter: Privacy-First Bill Splitting with Claude Vision
A technical deep-dive into building a stateless, multi-currency receipt splitter using Claude Vision OCR, Go Fiber, and React—with zero user data storage.