Kotlin Developer (f/m/x)

About the Position

Kotlin Developer (f/m/x)

Join Sii as a Senior Kotlin Developer for a fintech platform project focusing on seamless financial tool integration. Lead microservices development, collaborate across domains, and ensure high reliability and scalability.

Responsibilities

• Leading initiatives to design, build, and maintain scalable microservices primarily using Kotlin
• Collaborating with cross-functional teams to develop innovative solutions across Platform, Services, SMB, and other domains
• Analyzing system performance and implementing optimizations to ensure high reliability and scalability
• Participating in code reviews, post-mortems, and providing mentorship to other engineers
• Proactively improving the architecture and quality of solutions, and leading the team through technical challenges and migrations

Requirements

• Minimum 5 years of professional experience in software development
• Expertise in server-side languages, especially Kotlin, and experience with distributed systems, microservices, and cloud environments (e.g., AWS, Kubernetes)
• Proficiency with relational databases like PostgreSQL, testing frameworks (e.g., JUnit, Testcontainers), and observability tools like Grafana
• Strong problem-solving skills and a collaborative mindset to mentor and upskill your teammates
• Very good knowledge of English - min. B2 level
• Residing in Poland required

Nice to Have

• Previous work in the fintech industry or with financial products
• Knowledge of topics related to payments, cards, or accounting
• Experience working in a scale-up environment
• Proficiency in one of the following front-end technologies: React or TypeScript

Locations

• Bialystok, Poland
• Bydgoszcz, Poland
• Cracow, Poland
• Gdansk, Poland
• Katowice, Poland

We Offer

• Great Place to Work
• Solid financial situation
• Contracts with the biggest brands
• Centre of internal trainings
• Many experts you can learn from
• Open and accessible management team
• Profit sharing
• Passion Sponsorship program
• Regular integration events and trips
• Comfortable and well-equipped offices
• MySii app
• Medical care

About the Company

Since 2015, we have been recognized with the Great Place to Work title every year, a prestigious award based on employees feedback. According to the study, over 92% of people working at Sii consider it a fantastic place to work.