Senior Software Engineer

About the role: 

Appfire is looking for a Senior Java Software Engineer 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 Poland.

What you’ll do: 

• 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.
• Actively utilizing AI-assisted developer tools (e.g., Cursor, Claude Code) to boost daily productivity and participating in the technical implementation of AI-driven product features.

Technical Highlights:

• Add your value to a 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
• Enhance your engineering workflow by adopting state-of-the-art AI tools for code generation, refactoring, and debugging, while working on cutting-edge AI integrations
• Feel safe with our extensive CI process that automatically runs unit, integration, e2e, architecture, migration and performance tests on your commit

What you'll need:

• 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.
• AI & Modern Tooling: Hands-on experience working with AI coding assistants (like Cursor) and an eagerness to implement modern AI solutions (e.g., LLM integrations, RAG) into the product.
• 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).

Beyond the resume skills that match our culture and this role:

• 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.

What we offer:

• Contract of Employment (indefinite)
• Every Appfire team member is eligible for company equity, fostering a true sense of ownership and connection to our growth.
• 26 paid vacation days annually, regardless of tenure, 12 Wellness Days (1 day per month, non-transferable), 24 hours of paid volunteer time to engage in meaningful activities outside of work.
• Fully covered Luxmed private healthcare plan. You can extend coverage to your partner or opt for additional upgrades tailored to your needs. Life insurance provided by UNUM and fully paid by Appfire.
• MyBenefit Platform - 150 PLN per month to spend on a Multisport card or on a variety of experiences such as shopping, restaurants, and entertainment.
• Home Office Allowance - 200 PLN net per month added to your salary to support your electricity and internet costs while working remotely.
• Lunch Card - 300 PLN monthly for groceries or dining out, available via a virtual pre-paid Pluxee card.

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