About the Role

We are looking for a Senior Java Developer to work on the development and evolution of the Luminary Ledger platform. You will build and optimize high-performance backend services using Java 22 and Spring Boot, working with modern architectures, event-driven systems, and complex transaction workflows.

This is a fully remote role, ideal for an experienced backend engineer with strong architectural thinking and fintech or high-load system experience.

Key Responsibilities

1. Development & Architecture

• Further development and maintenance of the Luminary Ledger platform based on Spring Boot 3.x and Java 22
• Implementation of new features in transaction processing, account management, and reporting
• Development and optimization of State Machines for complex transaction workflows
• Design and implementation of REST APIs using OpenAPI/Swagger standards
• Working with Hexagonal Architecture (Ports & Adapters Pattern) to ensure clear layer separation

2. Database & Persistence

• Development and maintenance of PostgreSQL database schemas with over 48 Flyway migrations
• Optimization of JPA/Hibernate queries for performance-critical financial operations
• Design and implementation of Data Warehouse structures for reporting and analytics

3. Event-Driven & Asynchronous Processing

• Integration and development of Apache Kafka-based event systems
• Implementation of asynchronous transaction queues for highly available processes
• Working with Redis for distributed caching and performance optimization

4. Testing & Quality Assurance

• Creation of Cucumber BDD tests to ensure business logic
• Unit and integration tests with JUnit 5 and TestContainers
• Code reviews and adherence to code quality standards (Checkstyle, SonarQube, JaCoCo)

5. DevOps & Deployment

• Containerization with Docker and orchestration of microservices
• Working with Docker Compose for local development environments
• Collaboration on CI/CD pipelines and deployment processes

Requirements

1.Technical Expertise

• 5+ years of experience in professional Java development
• Strong knowledge of Spring Boot 3.x and Spring Ecosystem (Spring Security, Spring Data, Spring Kafka)
• Excellent knowledge of relational databases (PostgreSQL preferred) and JPA/Hibernate
• Experience with REST API development and API design principles
• Understanding of Microservices architectures and Clean Architecture patterns
• Confident use of Maven as a build tool
• Experience with Git and modern development workflows

2. Methodological Competencies

• Understanding of Domain-Driven Design (DDD) and Bounded Contexts
• Experience with Test-Driven Development (TDD) or Behavior-Driven Development (BDD)
• Knowledge of Object-Oriented Design and SOLID principles
• Ability to translate complex functional requirements into technical solutions

Nice-to-have

Advanced Technical Knowledge

• Experience with Apache Kafka and Event-Driven Architecture
• Knowledge of Redis and distributed caching strategies
• Experience with OAuth2/OpenID Connect and Spring Security
• Knowledge of Flyway or Liquibase for database migrations
• Experience with MapStruct for type-safe bean mapping
• Understanding of CQRS (Command Query Responsibility Segregation)
• Experience with State Machine Patterns and workflow engines

Domain Knowledge

• Experience in Banking/FinTech sector
• Knowledge of financial transaction processing
• Understanding of compliance requirements (AML, KYC)
• Experience with multi-currency systems

DevOps & Tools

• Experience with Docker and container orchestration
• Knowledge of Kubernetes or similar platforms
• Experience with CI/CD pipelines (Jenkins, GitLab CI, GitHub Actions)
• Knowledge of Monitoring and Observability (Prometheus, Grafana, ELK-Stack)
• Experience with SonarQube for code quality management

Testing:

• Experience with Cucumber and Gherkin syntax
• Knowledge of TestContainers for integration tests
• Performance testing and load testing experience

Technology Stack in Detail

Language & Version Java 22

Framework Spring Boot 3.4.1, Spring Security, Spring Data JPA, Spring Kafka

Build & Dependencies Maven 3.x, MapStruct 1.6.3, Lombok 1.18.38

Database PostgreSQL 42.7.4 with Flyway 11.1.1 (48 migrations)

ORM Hibernate/JPA 6.6.4

Caching Redis (Spring Data Redis, Spring Cache)

Messaging Apache Kafka with SASL authentication

API & Documentation SpringDoc OpenAPI 2.8.1, Swagger UI

Security OAuth2 Resource Server, JWT, Keycloak

Testing JUnit 5, Cucumber 7.18.0, TestContainers, JaCoCo

Code Quality Checkstyle 3.4.0, SonarQube, Maven Checkstyle Plugin

Scheduled Tasks ShedLock 5.14.0 (Distributed Locking)

Logging SLF4J 2.0.16

JSON Processing Jackson 2.17.2

Containerization Docker, Docker Compose