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# Backend Developer

- **Company:** CGI
- **Location:** Madrid, Spain (Remote available)
- **Salary:** €52,000.0 - €68,000.0
- **Contract:** Permanent contract
- **Skills:** Automation of Tests, Data Structures, Interoperability, Java Virtual Machine (JVM), Junit, PostgreSQL, OAuth, Fast Healthcare Interoperability Resources, Spring-boot, Reliability of Systems, Backend, Kotlin, Health Level Seven International, Api Design
- **Published:** September 24, 2026
- **Apply:** https://www.adzuna.es/contact-us.html

## About the Role

Strong experience in backend development using Kotlin and/or JVM-based technologies
Solid hands-on experience with Spring Boot in production environments
Proven ability to build or contribute to high-abstraction systems such as query engines, rule engines, or dynamic processing frameworks
Strong knowledge of PostgreSQL, including advanced querying and JSONB data modeling
Experience writing and maintaining comprehensive automated test suites using JUnit
Ability to work collaboratively within a small engineering team and align on shared architectural decisions
Strong communication skills with fluent English (minimum B2 level) for daily technical collaboration
Comfortable working remotely within Europe and engaging in distributed team workflows
Bonus: familiarity with HL7 FHIR (R4), HAPI FHIR, or healthcare data systems
Bonus: experience with OAuth flows, identity providers such as Zitadel, or authorization systems like SpiceDB

## Description

This role is part of a highly technical healthtech initiative focused on rebuilding a core FHIR server from the ground up. You will be working on complex, abstraction-heavy backend engineering challenges, going far beyond standard API development. The primary focus is the design and implementation of a dynamic query engine capable of interpreting flexible parameters and FHIR structure definitions at runtime. You will join an existing team of engineers and contribute to a shared architecture, working collaboratively on design decisions and system evolution. The environment is deeply technical, with strong emphasis on scalability, correctness, and healthcare interoperability standards. This is a hands-on role where your work will directly influence the backbone of modern healthcare data infrastructure.
Accountabilities:
Design and implement high-abstraction backend components, with a focus on a dynamic query engine for FHIR-based data structures
Contribute to the development of a custom FHIR server built in Kotlin and Spring Boot
Collaborate with a small engineering team to define architecture, split tasks, and align on technical direction
Develop and maintain robust backend services using PostgreSQL, including JSONB-based data modeling and complex queries
Build and expand comprehensive automated test coverage using JUnit to ensure system reliability
Integrate and work with healthcare data standards such as FHIR R4 where applicable
Participate in technical discussions, surfacing blockers and refining system design with the team
Support secure authentication and authorization patterns using OAuth and identity management systems
Ensure backend systems are scalable, maintainable, and aligned with long-term platform goals


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