Open to opportunities

Andrei User

@andreiuser4

Message

Senior Java backend engineer building secure, event-driven microservices on GCP and Kafka.

Poland

Message

What I'm looking for

I’m looking to deliver secure, event-driven Java systems where I can lead technically, reduce toil through automation, and mentor teams—ideally in regulated environments that value quality, performance engineering, and reliable operations.

I’m a hands-on Java technologist with over 12 years of experience delivering robust production code. I focus on the modern Java ecosystem—Java 21, Spring Boot 3.x, and JVM internals—to make enterprise systems faster, safer, and easier to operate.

I build secure, event-driven microservices architectures on GCP using GKE and Kafka, applying Zero Trust Architecture concepts like OAuth2 and OpenID Connect to mitigate risks across distributed systems. I also lead support and delivery efforts through Root Cause Analysis (RCA), hot-fixes, and process improvements that reduce toil.

I enjoy mentoring engineering communities, constructively challenging existing thinking, and translating business opportunities into scalable technical solutions. With regulated financial-sector experience (banking, insurance, and integration systems), I’m comfortable with presale work and direct customer collaboration.

Experience

Work history, roles, and key accomplishments

Current

Independent Engineer

Current

Independent Developer

Jan 2026 - Present (5 months)

Built an Android-based vehicle telemetry and diagnostics system integrating OBD-II scanners via Bluetooth (SPP/BLE) and Wi‑Fi, with offline scan history and shareable PDF reports. Developed cloud-native Java services for automated IT job aggregation and AI-assisted vacancy matching using Kafka event processing and OAuth2/OIDC security.

Kotlin Android SDK Jetpack Compose Bluetooth (BLE SPP) & OBD2 Java 21 Virtual Threads (Project Loom)Apache Kafka PostgreSQL OAUTH2

Backend Developer (Freelance)

Freelance

Mar 2009 - Nov 2009 (8 months)

Developed server-side functionality for a city event aggregator platform including search, event recommendations, and ticket booking, plus custom integrations with external systems. Built administrative views for event participation and statistics.

Java PostgreSQL Maven IBatis JDBC