Senior Java Backend Developer

Ubique Systems; Kraków; Presencial; PLN 180 000 - 280 000; Tempo integral

Resumo da oferta

Ubique Systems in Kraków is seeking an senior software engineer to design, build, and optimize Java Spring Boot microservices for order and trade workflows. You will implement REST/GraphQL APIs, integrate with Kafka/ActiveMQ, and drive real-time data processing across AWS serverless stacks.

The role requires 8+ years in Java, experience with databases like PostgreSQL/MongoDB, and strong testing, CI/CD, and collaboration skills in an Agile environment.

Qualificações

• 8+ years of hands-on Java software engineering in large-scale environments.
• Bachelor’s or Master’s degree in Computer Science, Engineering, or related field.
• Experience building scalable Java microservices with Spring Boot and designing REST/GraphQL APIs.
• Experience with event-driven messaging using Kafka and ActiveMQ.
• Experience delivering through CI/CD pipelines and automated testing.
• Experience with GenAI/LLM app development (RAG, vector DBs, Spring AI).

Responsabilidades

• Design, build, and enhance Java Spring Boot microservices and APIs.
• Build event-driven integrations using Kafka/ActiveMQ for real-time flows.
• Develop AWS serverless solutions and manage data in PostgreSQL and MongoDB.
• Apply CI/CD, secure SDLC, and automated testing with JUnit/Mockito.
• Optimize performance of low-latency, high-throughput services.
• Develop GenAI/LLM capabilities (RAG, vector DBs, Spring AI).
• Collaborate with Product Owners, Architects, and engineers; participate in code reviews.
• Apply DevOps practices: monitoring, logging, operational readiness.
• Support modernization toward cloud-native architectures.

Conhecimentos

Java

Spring Boot

Microservices

REST APIs

GraphQL

Kafka

ActiveMQ

AWS

Lambda

API Gateway

S3

DynamoDB

PostgreSQL

MongoDB

JUnit

Mockito

GenAI/LLM

RAG

Spring AI

Agile

Collaboration

Communication

Formação académica

Bachelor’s or Master’s degree in Computer Science or related field

Ferramentas

Kafka

ActiveMQ

AWS

CloudFormation

PostgreSQL

MongoDB

JUnit

Mockito

Spring Boot

Spring MVC

Spring Data

GenAI tooling

Descrição da oferta de emprego

• Design, build, and enhance Java Spring Boot microservices and REST and GraphQL APIs across the order and trade lifecycle, including order capture, validation, routing, execution, allocation, and booking.


• Build event‑driven integrations using Kafka and ActiveMQ to deliver reliable, real‑time order and trade flows.


• Develop AWS serverless solutions using Lambda, API Gateway, S3, Step Functions, DynamoDB, and CloudFormation, and manage data on PostgreSQL and MongoDB.


• Apply engineering best practices, including clean code, CI/CD, secure SDLC, and automated testing with JUnit and Mockito.


• Optimize the performance of low‑latency, high‑throughput services, contributing to resilient and scalable trading systems.


• Build GenAI and LLM capabilities using retrieval‑augmented generation (RAG), vector databases, and Spring AI to enhance order and trade workflows.


• Collaborate closely with Product Owners, Architects, and engineers, and contribute to code reviews, testing strategies, and trouble shooting of complex technical issues.


• Apply DevOps practices, including monitoring, logging, and operational readiness in delivered solutions.


• Support modernization efforts by helping evolve legacy systems toward modular, cloud‑native, and event‑driven architectures.

Your expertise

Software engineering & technical skills

• Strong hands‑on experience in Java, building scalable microservices with Spring Boot, Spring MVC, and Spring Data, and designing REST and GraphQL APIs.


• Experience with event‑driven messaging using Kafka and ActiveMQ, and with data stores such as PostgreSQL and MongoDB.


• Experience delivering through CI/CD pipelines with automated testing using JUnit and Mockito, and applying performance optimization, reliability, and secure development practices to low‑latency, high‑throughput services.


• Hands‑on experience with GenAI/LLM application development, including RAG, vector databases and Spring AI.


• Ability to contribute hands‑on to development and problem solving of complex technical challenges.


• Experience working in Agile delivery models.


• Strong collaboration skills across engineering, product, and architecture teams.


• Ability to communicate technical concepts effectively with both technical and non‑technical stakeholders.

Qualifications

• Bachelor’s or Master’s degree in Computer Science, Engineering, or a related field (or equivalent experience).


• 8+ years of hands‑on Java software engineering experience within large‑scale or complex environments.

Nice to have

• Exposure to order management, trade execution, or trading platforms in financial services or wealth management.


• Experience contributing to engineering standards, best practices, or shared components.