OverviewSenior Backend Engineer at a fast-growing technology company where software and engineering excellence are core.
You will help maintain and evolve a transactional, platform-focused backend, shaping architecture and cloud-native modernization.
You'll work with cross-functional teams to build scalable services and improve reliability and observability.
This role offers ownership, collaboration, and opportunities to participate in strategic technical decisions within an international, growth-driven environment.
Compensaciones / BeneficiosPermanent contract
Hybrid working model
Versátil working hours
Continuous learning and professional development
International environment
Competitive salary package
ResponsabilidadesDesign and develop robust backend services using Kotlin
Build and maintain scalable REST APIs and distributed microservices
Participate in architectural discussions focused on scalability, performance, and maintainability
Contribute to migration and modernization of cloud-native services
Improve reliability, observability, and operational excellence
Manage services with a DevOps mindset from requirements analysis to production




Identify recurring operational issues and implement automated solutions
Collaborate with engineering teams to share knowledge and improve development practices
Support adoption of modern engineering standards, testing strategies, and platform tooling
Requisitos principales5+ years of professional Kotlin experience
Backend development with Kotlin, Spring Boot (highly valued) and Quarkus (highly valued)
Experience designing, developing, and maintaining RESTful APIs
Strong understanding of microservices and distributed systems
Experience with PostgreSQL, MySQL, MongoDB
Git and collaborative development workflows
Cloud platforms experience, preferably Google Cloud Platform (GCP)
CI/CD pipelines and deployment automation
Kubernetes and GitOps tools such as Terraform, Helm, or Flux
Monitoring and observability tools such as Grafana, Prometheus, Kibana
Software design patterns, testing strategies, and Clean Code principles
Excellent written and spoken English
collaboration
ownership
strong communication
Kotlin
Spring Boot
Quarkus

📌 Senior Kotlin Fullstack Developer (Barcelona)
🏢 Hays
📍 Barcelona