Java Tech Lead

Quick Facts

Role: Java Tech Lead

Collaboration model: B2B, hybrid (1x per week on-site with the client in Warsaw)

Description

Lead backend development for Java and Spring Boot systems, designing and evolving microservices-based solutions. Build resilient and scalable services using DDD and hexagonal architecture, and implement integrations via REST/SOAP and Apache Kafka. Take ownership of technical decisions, quality, and performance, including code reviews and test strategy.

Responsibilities

• Design and develop backend applications in Java and Spring Boot
• Act as a technical lead and support the team in technology decisions
• Design and develop microservices and hexagonal-architecture systems
• Apply Domain-Driven Design (DDD) in solution design
• Design and implement system integrations using REST, SOAP, and Kafka
• Ensure high availability, scalability, and fault tolerance in distributed systems
• Optimize performance and diagnose technical issues
• Maintain code quality, engineering standards, and best practices
• Conduct code review and help resolve complex technical problems
• Use AI tools to improve the software delivery process

Requirements

• Java 11+ expertise
• Practical experience with Spring Framework and Spring Boot 3.5+
• Experience with Hazelcast or Redis
• Hands-on experience with JPA and Hibernate
• Strong microservices and hexagonal architecture knowledge
• Practical Domain-Driven Design (DDD) experience
• Experience integrating systems using SOAP, REST, and Apache Kafka
• Strong SQL skills and relational DB experience with PostgreSQL and Oracle
• Knowledge of design patterns and integration patterns
• Experience designing resilient solutions for distributed systems
• Understanding of SOLID, DRY, and KISS principles
• Ability to design and implement different test types
• Experience with diagnostics, monitoring, and application performance optimization
• Ability to effectively use AI tools in software development
• Ability to make technical decisions and work effectively with a developers team

Benefits

• Transparent B2B cooperation with opportunities matched to your skills and preferences
• Dedicated contract owner as your primary contact for project organization and next opportunities
• Training, certifications, and conferences—participation rules set individually
• Community involvement (webinars and other initiatives)
• Sports activities and access to shared training rooms
• Optional additional services (private medical care, sports card, insurance, psychological support)
• Cafeteria platform to choose services/products using allocated points