About

Hi, I’m John — a backend and infrastructure engineer with 6+ years of hands-on experience building reliable distributed systems, self-hosted cloud infrastructure, and modern web applications.

Core Expertise

• Backend & Distributed Systems: Go, gRPC, Istio, microservices architecture, high-concurrency locking & caching, PostgreSQL.
• Infrastructure & Cloud Native: Bare-metal binary Kubernetes HA deployments, Linux internals (epoll, networking, kernel tuning), Docker, Coolify, self-hosted CI/CD.
• Full-Stack & Edge: Next.js, Astro, Tailwind CSS, Cloudflare Pages / Workers / D1 / R2.
• Real-World Operations: Bridging software architecture with practical B2B business workflows, ERP/CRM integrations, and global static/edge performance.

What I Write About

This site (john.janrs.com) is where I document practical engineering guides, production debugging notes, and architecture deep dives — including my bare-metal Kubernetes HA series and Linux I/O notes.

Connect

• GitHub: github.com/janrs-io