Overview At Q-tech , we're looking for a Senior Java Engineer to join a integral SaaS product that's scaling fast and moving into a more mature, reliability‐focused phase.
The platform handles a high volume of data and workflows used by customers across multiple countries. The team is strengthening its foundations to ensure stability, consistency and long‐term scalability — and they're looking for someone who can take a leading role on the Java side.
You'd become the Java reference point : someone who can set technical direction, build new services with Java + Spring + PostgreSQL , and help elevate the platform's engineering standards. There's also some existing functionality in Node.js , and part of the work involves gradually moving that logic into the new Java‐based architecture.
This isn't a "ship fast and patch later" environment. Quality matters: clean architecture, solid testing, strong patterns, observability, and a product that needs to behave predictably for demanding clients.
What you'll do Design and build backend services using Java + Spring
Bring architectural vision,
patterns, and best practices
Help migrate existing Node.js components into the new Java stack
Work with clean/hexagonal architecture and rich domain models
Collaborate with a senior team and a technically strong CTO
Make autonomous technical decisions that shape the platform
Requirements 6+ years of experience working with Java in complex or high‐reliability environments
Strong expertise with Spring and the ability to design services from scratch
PostgreSQL experience is a must (data modelling, performance, migrations, consistency)
Solid understanding of clean/hexagonal architecture , domain‐driven thinking and tactical patterns
Strong testing mindset and familiarity with CI/CD and engineering best practices
Ability to review, challenge and elevate the team's technical decisions
Experience working with existing codebases and migrating functionality is a plus (some parts currently in Node.js
📌 Senior Java Engineer (Madrid)
🏢 Q-Tech
📍 Madrid