Backend Engineer
Building reliable integrations and observable distributed systems.
Years
8+
Projects delivered
19
Users
200K–300K
RelayHub
connecting…Impact
Numbers behind the focus areas
Outcomes, not claims — the scale and results this experience has actually been applied at.
8+
Years
Backend engineering, system integration, and production operations.
19
Projects delivered
Production delivery across identity, AI, enterprise, and cloud systems.
200K–300K
Users
Peak authentication traffic supported by a Redis-based SSO architecture.
20+ → ~1
Consistency incidents / week → / month
Cross-system transaction-consistency incidents reduced via preventive controls.
<5s
AI pipeline latency
Typical end-to-end STT → translation → TTS time for 3–4 spoken sentences.
10
Concurrent recipients
Validated real-time voice delivery capacity per WebSocket channel.
Projects
Featured projects
Written as problem, architecture, decisions, failure handling, and result — not a technology list.
RelayHub
LiveEvent-driven Integration Platform
An event-integration platform: events are ingested, validated, transformed, and delivered to downstream targets with retry, dead-letter handling, replay, and metrics — this site's Live Monitoring page reads its real, live delivery and DLQ data directly.
- Java
- Spring Boot
- Kafka
- PostgreSQL
English Core Speaking
LiveUser-facing Learning SaaS
A full-stack English speaking practice service: a NestJS backend and Vue 3 frontend, with OAuth-based sign-in and an external AI/LLM API integration for evaluating spoken responses.
- NestJS
- Vue 3
- PostgreSQL
- Prisma
Focus
Engineering focus
- Backend Engineering
- Enterprise Integration
- Transaction & Data Consistency
- Auth & Identity Integration
- Distributed & Event-driven Systems
- Production Troubleshooting
- AI / LLM Integration
Case Studies
Selected case studies
Abstracted production engineering scenarios: investigation, root cause, trade-offs, and lessons learned.
A Race Condition in Distributed Delivery Processing
An asynchronous delivery pipeline occasionally left a downstream record in an inconsistent state when a delete and a create for the same logical entity raced each other. This is a composite, abstracted scenario representative of enterprise integration work — no real company, customer, or system names are used.
Timeout and Concurrency Issues in an External-Approval Rollback Flow
A workflow that depended on an external system's approval step had a rollback path that assumed the approval call would complete quickly and exactly once. Neither assumption held under real conditions. This is a composite, abstracted scenario — no real company, customer, or system names are used.
Platform
Architecture & platform snapshot
Every project here runs on the same Hetzner k3s cluster, behind a single shared Gateway, deployed by its own CI pipeline.
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