Role Description Appfire is looking for a Senior Backend Java Developer to help evolve a modern, cloud-based SaaS platform. You’ll design new backend functionality, optimize existing services, and support systems used by thousands of tenants. This role reports to the Senior Manager of Engineering and works cross-functionally with product, UX, and frontend partners to deliver reliable, well-tested SaaS solutions. You can choose to work remotely from anywhere in Bulgaria. Your everyday tasks will include: - Designing and implementing new functionalities while maintaining and optimizing existing ones. - Ensuring high code quality through rigorous testing (unit, integration) and peer code reviews. - Collaborating with Product Owners, UX/UI designers, and frontend teams. - Solving performance-related challenges to ensure system stability and speed. - Contributing to technical discussions and helping the team solve production issues. Technical Highlights: - Add your value to complex yet well-designed application, having over 100 modules and fully-fledged Domain-Driven Design (ubiquitous language, aggregates, domain events etc.) - Practice your craftsmanship in good design (clean code, SOLID, Inversion of Control) and in various architectures (hexagonal, event-driven, pipes&filters, modular monoliths, microservices and more) - Thoroughly test what you build: with unit, integration and e2e tests (Spock, JUnit, Mockito, AssertJ, REST Assured, WireMock, Testcontainers, Cypress) - Learn our advanced cloud (SaaS) architecture: serving thousands of tenants (multitenant architecture), continuously monitored and profiled (ELK, async-profiler), and with state of the art release process (feature flags, canary releases). We use AWS and GCP. Help us advance our cloud architecture further - Practice other cool approaches and tools like reactive programming, Event Sourcing, Apache Kafka or Redis - Feel safe with our extensive CI process that automatically runs unit, integration, e2e, architecture, migration and performance tests on your commit Qualifications - Solid Java Foundation: Strong practical knowledge of Java, Spring, Hibernate, and SQL. - Clean Code & Patterns: A good understanding of SOLID principles and common design patterns to keep the codebase maintainable. - Testing & Tools: Proficiency in JUnit/Spock, Git, Maven, and Docker. - Production-Ready Mindset: Experience in evolving and scaling established systems (beyond just greenfield projects) and a focus on long-term code maintainability. - Performance Awareness: Ability to use profiling tools and a focus on writing efficient code that performs well under load. - Cloud Basics: Understanding of SaaS architecture and cloud environments (AWS or GCP). Requirements - You are dedicated to elevating client and co-worker experiences, knowing that exceptional work centers on serving others. - You adapt swiftly to new business demands, understanding that change fuels collective and individual growth. - You excel in communication, effectively connecting in remote/hybrid environments using tools like Slack, Zoom, and G Suite and through occasional in-person events. - You have exceptional coaching, mentoring, and people development skills. Benefits - 25 paid days off, regardless of years of experience - Private healthcare - Sofia public transport card - Multisport card - Development opportunities via our Appfire University