Senior Java Developer (AppSec.Hub)

Swordfish Security Senior Java Developer (AppSec.Hub) Experience: over 6 years Full-time employment Schedule: 5/2 Work format: remote or hybrid or office

☑️ Responsibilities

• Design and develop core microservices in Java 17 / Micronaut (without Spring)
• Work with event-driven communication: all inter-service communication is via a message broker, async-first, database-per-service, eventual consistency
• Solve high-load processing tasks: multithreading, non-blocking I/O, optimization for GC and JIT
• Work with data: PostgreSQL (via MyBatis), analytics on ClickHouse, cache and read models on Redis
• Handle observability (metrics/logs/tracing) — this is currently a growth area in the services
• Actively use AI-assisted development (Claude) — this is part of our daily process
• Event-driven microservices with a focus on performance and
• Core: Java 17 + Micronaut (without Spring), embedded Netty. Lightweight framework and targeted libraries, direct control over threads, I/O, and memory
• Communication: asynchronous, via broker (LavinMQ / AMQP) — async-first, database-per-service, eventual consistency
• Data: PostgreSQL (MyBatis), ClickHouse, Redis
• Contracts: Protocol Buffers (messages) + OpenAPI 3.1 (REST)
• Operations: Docker / Kubernetes

☑️ Candidate Requirements -Java 17 at the platform level; Micronaut 4.x (without forced -dependency on Spring) -I/O: io / nio / nio2; understanding of the embedded HTTP server (Netty) -Stream API -Multithreading and concurrency, understanding of JMM -Understanding of JIT and GC, ability to diagnose and optimize -GraalVM / native-image -Confident work with relational databases and understanding of their internal workings: transactions and isolation, indexes, scheduler, connection pool. Primarily PostgreSQL (MySQL / other relational DBs are fine, the model is important) -MyBatis (over JDBC) and migrations (Liquibase) -ClickHouse (analytics / eventstore) -Redis (cache, read models CQRS) -AMQP: LavinMQ / RabbitMQ — producers/consumers, exchange types (direct/topic/fanout) -Reliability patterns: idempotence, at-least-once, retries, eventual consistency, backpressure -Protocol Buffers (proto3) for message serialization (not gRPC- -RPC) -HTTP/1.1 and HTTP/2 -Docker, Kubernetes -Observability: metrics, logs, distributed tracing -Vibecoding: prompt engineering for Claude, using skills and subagents -Mandatory selection criterion: bring a live, non-trivial Java project — we will review it together

Contacts: recruiter contact