Senior Full-Stack Developer (Kotlin/Java)

About the Position

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At Intellias, we are seeking a Senior Full-Stack Developer with expertise in Kotlin/Java to join our international team for a long-term project in the transportation and supply chain domain. This role offers the opportunity to work remotely from Bulgaria, Croatia, Poland, Portugal, or Spain.

Responsibilities

• Take end-to-end ownership of product features, from technical design and implementation to release, monitoring, and production support
• Develop new mobile functionality and supporting backend services
• Translate business and product needs into reliable and maintainable technical solutions
• Design clear interfaces and data flows between mobile, backend, database, and messaging components
• Implement reliable offline behavior and data synchronization mechanisms
• Maintain high engineering standards through automated testing, code reviews, and static analysis
• Investigate and resolve complex issues across multiple application layers
• Improve application performance, stability, security, and scalability
• Contribute to architectural decisions and propose improvements to existing solutions
• Identify and address technical debt as part of ongoing development
• Support automated build, delivery, and deployment processes
• Collaborate closely with mobile, backend, cloud, product, and other cross-functional specialists
• Share technical knowledge and mentor other engineers where appropriate

Requirements

• 6+ years of professional software development experience
• Strong production experience across both Android/Kotlin and Java/Spring Boot, with senior-level expertise in at least one of these areas
• Strong knowledge of Kotlin, Android SDK, and modern native Android development
• Hands-on commercial experience with Jetpack Compose
• Practical experience with Kotlin Coroutines, Flow, StateFlow, and SharedFlow
• Strong understanding of MVVM or MVI, Clean Architecture, and multi-module Android applications
• Experience with Hilt or Dagger and Android Jetpack components, including ViewModel, Navigation, Room, WorkManager, and DataStore
• Experience with offline synchronization, REST API integration, and JSON serialization
• Strong Java and Spring Boot development experience, including microservices and REST API design
• Solid knowledge of JPA, Hibernate, SQL, relational databases, transaction management, and query optimization
• Experience with asynchronous and event-driven solutions using Apache Kafka or similar messaging technologies
• Good understanding of distributed systems, service-to-service communication, caching, error handling, and resilience patterns
• Hands-on experience with Docker, Kubernetes, Microsoft Azure, and preferably Azure Kubernetes Service
• Experience with Gradle, Maven, Git, and automated CI/CD pipelines, preferably GitLab CI/CD
• Strong testing experience covering unit, integration, API, and mobile UI testing using relevant frameworks such as JUnit, Mockito, Testcontainers, and Jetpack Compose UI testing
• Good understanding of application security, including OAuth2/OIDC, JWT, HTTPS/TLS, secure API design, secrets management, and OWASP principles
• Experience with application performance analysis, production troubleshooting, crash investigation, and monitoring
• Ability to make independent technical decisions, review code, and contribute to architecture discussions
• Upper-Intermediate or higher English communication skills

Nice to Have

• Kotlin Multiplatform or.NET MAUI
• GraphQL, Kafka Streams, Redis, NoSQL, or Azure Service Bus
• Helm, Terraform, or other Infrastructure as Code tools
• Domain-Driven Design, CQRS, or Event Sourcing
• BLE or other hardware integration experience
• Firebase, Crashlytics, Sentry, Azure Monitor, Application Insights, Prometheus, or Grafana
• Experience modernizing legacy Java applications
• Experience with large-scale enterprise systems
• German communication skills

We Offer

• Join a team that values equity, diversity, and inclusion
• A range of benefits that support your well-being and professional growth
• Opportunity to work on advanced tech challenges with a global team

About the Company

At Intellias, where technology takes center stage, people always come before processes. By creating a comfortable atmosphere in our team, we empower individuals to unlock their true potential and achieve extraordinary results. Join Intellias for a career where your perspectives and contributions are vital to our shared success.