Senior Java Developer
Senior backend developer designing high-volume data integration and transformation processes for a European travel booking platform, using Java, Spring Boot, Kafka, MySQL, and microservices with hexagonal architecture in the cloud. Starts as a freelance contractor on a European timetable, with visa sponsorship and relocation support to the Bilbao area later.
- Compensation
- Not disclosed
- Location
- Barakaldo, Spain
- Work setup
- Not specified
- Seniority
- Senior
- Employment
- Contract
- Experience
- 6+ years
- Category
- Software engineering
- Posted
Skills
Must have
- 6+ years of experience as a Backend Developer with Java (8, 11, or 17)
- Mastery of Spring Boot
- Experience with Big Data and relational databases (preferably MySQL)
- Microservices architecture experience (monolith-only candidates not considered)
- Practical knowledge of Hexagonal Architecture
- Fluent conversational English (minimum B2), daily work in English
- Unit testing proficiency
- Experience with Pair Programming
Nice to have
- Knowledge of Spring Batch
- Experience with Kotlin
- .NET project experience alongside solid Java
- Universal REST API connections
- Build automation tools (Maven) and version control (Git)
- Multithreading, performance optimization, and resource management (Memory/CPU)
- Integrating AI into the daily workflow as a fundamental mindset
Full description
This position is for an international travel-tech company with over 20 years of experience and a strong presence across several European countries.
The company specializes in digital travel booking solutions, working with cutting-edge technologies in a multicultural environment that fosters collaboration and technical excellence.
What will your day-to-day look like?
- Design and implement integration and transformation processes for high-volume data.
- Work with Spring Boot, Kafka, MySQL databases, and modern technologies in cloud environments.
- Actively participate in architectural decisions: microservices, hexagonal design, and a modular, scalable approach.
- Collaborate with a technical team that values shared knowledge, healthy high standards, and continuous learning.
- Contribute to a solution used across multiple European countries that is constantly evolving.
Note: This is a purely technical position focused on individual contribution;
there are no immediate paths to management or increased non-technical responsibility.
Mandatory Requirements
- 6+ years of experience as a Backend Developer with Java (8, 11, or 17) .
- Mastery of Spring Boot. Knowledge of Spring Batch is highly valued.
- Experience with Big Data and relational databases (preferably MySQL).
- Microservices architecture experience (candidates with only monolith experience will not be considered).
- Practical knowledge of Hexagonal Architecture.
- Fluent conversational English (minimum B2) , as you will work daily in English.
- Unit testing proficiency.
- Experience with Pair Programming.
We also highly value experience in:
- Kotlin , even if it is not your primary language.
- .NET projects , provided you maintain solid experience in Java.
- Universal REST API connections.
- Build automation tools (Maven) and version control (Git).
- Multithreading , performance optimization, and resource management (Memory/CPU).
AI Mindset
We are looking for professionals who integrate AI into their daily workflow as a fundamental mindset, going beyond coding to optimize tasks, preparation, and communication.