Senior Java Engineer (Remote within Spain)

Overview

At Q-tech, we’re looking for a Senior Java Engineer to join a global 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)
• Autonomy to make technical decisions without constant oversight
• Good communication skills and a collaborative mindset
• Based in Spain (remote)
• Experience collaborating with distributed and multicultural teams

What the role offers

• Become the go-to Java expert in the company
• Build critical components from scratch
• A real technical challenge with direct product impact
• A stable environment focused on doing things properly
• Remote work from anywhere in Spain + optional offices in several cities

• 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)
• Autonomy to make technical decisions without constant oversight
• Good communication skills and a collaborative mindset
• Based in Spain (remote)
• Experience collaborating with distributed and multicultural teams

• Become the go-to Java expert in the company
• Build critical components from scratch
• A real technical challenge with direct product impact
• A stable environment focused on doing things properly
• Remote work from anywhere in Spain + optional offices in several cities