PayPay Architecture: Scaling Payments to 70M Users

Answer-first: An in-depth look at PayPay’s engineering stack: handling 70M users and 7.8B transactions/year using TiDB, Kafka event sourcing, GitOps, and chaos engineering. PayPay launched in October 2018 and grew to 10 million users in just 3 months — a growth rate that no Japanese fintech had ever seen. By 2025, the platform had crossed 70 million registered users and processed 7.8 billion payments per year. Behind this growth is an engineering team that has had to scale not just their infrastructure, but their entire engineering culture: from service standardization and GitOps-driven deployments to chaos engineering and AI-powered fraud detection. ...

June 1, 2026 · 12 min · Lê Tuấn Anh

Autonomous Hybrid-AI Pipeline: Cron to State-Machine

It’s easy to write a cron job that pings an API, hands a URL to OpenAI, and publishes a markdown file. It’s significantly harder to orchestrate a distributed swarm of AI agents that can read deeply from diverse sources, deduplicate state across time, evaluate article quality through a multi-layer gate, safely publish via GitOps, and optimize its own power footprint—all without human intervention. In this deep tech dive, I will walk you through the complete architecture of my V3 Autonomous Content Pipeline. We’ll cover the shift from a time-based monolithic script to a state-based orchestration model, the engineering behind a 3-tier Hybrid AI routing strategy that crashes token costs from ~$3.50/day to nearly $0.05/day, and how to operate a physical GPU cluster with Wake-On-LAN to drive hardware electricity costs near zero. ...

May 18, 2026 · 15 min · Lê Tuấn Anh

Tech Radar, May 3, 2026: Dapr AI, R3F WebGPU, and Argo CD 3.4

Today’s Tech Radar tracks three massive architectural shifts occurring simultaneously across the backend, frontend, and infrastructure ecosystems in 2026. On the backend, the Dapr project has stabilized its Agents v1.0 framework for Agentic AI. On the frontend, React Three Fiber (R3F) has successfully bridged the gap to WebGPU via the Three Shading Language (TSL). At the infrastructure layer, the upcoming Argo CD 3.4 release introduces critical “Day 2” operational safety mechanisms for Kubernetes GitOps. ...

May 3, 2026 · 4 min · Lê Tuấn Anh

Tech Radar, May 2, 2026: 24-Hour TechTask Signals - Commerce Modernization Is Becoming an Operations Problem

The strongest TechTask signal in the last 24 hours is not a single framework release. It is the way several platform updates are converging on the same message: commerce modernization is no longer mainly about decomposing a monolith. It is about operating the decomposed system safely. That matters directly for the engineering profile behind this site: Strangler Fig migration from Magento/PHP into a 21-service Golang ecosystem, Dapr Pub/Sub for distributed workflows, Saga compensation for checkout and payment failure, Transactional Outbox for reliable events, GitOps through Kubernetes and ArgoCD, and performance work that pushed p95 latency from 1.2s to 120ms under high-traffic commerce load. ...

May 2, 2026 · 8 min · Lê Tuấn Anh

Tech Radar, April 23, 2026: Kubernetes v1.36 Haru Ships 18 GA Features and Closes the Lifecycle Gap

Kubernetes v1.36 “Haru” shipped on April 22, 2026, one day ago. The release carries 70 enhancements: 18 to stable, 25 to beta, 25 to alpha. After reading the full release notes and the detailed pre-release analysis directly from the source material, the picture that emerges is not a flashy feature drop. It is a release that closes several long-standing lifecycle gaps, hardens the security model in ways that matter for production, and makes a meaningful architectural bet on Dynamic Resource Allocation as the future of GPU and AI workload management. ...

April 23, 2026 · 10 min · Lê Tuấn Anh

Tech Radar, April 18, 2026: Argo CD Turns GitOps Into a Full Lifecycle Discipline

The selected items for pipeline run 32 all revolve around GitOps, but they do more than repeat the same story. After fetching and reading the full source material directly from the original URLs, a clear pattern emerges: GitOps in 2026 is no longer just about syncing manifests from Git to Kubernetes. It is becoming a disciplined lifecycle model for platform operations, with deletion safety, stronger reconciliation semantics, clearer governance boundaries, and increasingly explicit tradeoffs between centralized and decentralized control planes. ...

April 18, 2026 · 8 min · Lê Tuấn Anh

GitOps at Scale: Kubernetes & ArgoCD for Microservices

Answer-first: Why kubectl apply is dangerous. Learn how to automate a 21-service Go platform using ArgoCD App-of-Apps, Kustomize, and git revert rollbacks. Building 21 well-architected Go microservices is only half the battle. If your deployment process relies on an engineer running kubectl apply from their laptop on a Friday afternoon, you haven’t built an enterprise platform — you’ve built a ticking time bomb. When designing this composable e-commerce ecosystem, we made one hard architectural rule from day one: no human touches the production cluster directly. Everything flows through Git. ArgoCD enforces it. ...

April 12, 2026 · 7 min · Lê Tuấn Anh