Kotlin Backend Engineer - Fintech Microservices

Sii Poland; Lublin; On-site; PLN 180,000 - 300,000; Full time

Benefits offered by this job

Profit sharing

Medical care

Centre of internal trainings

Regular integration events and trips

Open management team

Job summary

Sii Poland is hiring a Kotlin backend developer to design, build, and maintain microservices for a modern fintech platform. The role involves collaborating with cross-functional teams across Platform, Services, SMB, and other domains to deliver robust solutions and improve system reliability.

The ideal candidate has at least 3 years of experience in software development, hands-on Kotlin in commercial projects, and familiarity with cloud environments and databases.

Qualifications

• Minimum 3 years of professional software development experience.
• Hands-on Kotlin experience in commercial projects.
• Experience building backend systems and microservices architecture.
• Cloud exposure (AWS, Kubernetes).
• Relational databases (PostgreSQL) and testing/observability tools (JUnit, Grafana).
• Good command of English; residing in Poland is required.

Responsibilities

• Design, build, and maintain Kotlin-based microservices.
• Collaborate with cross-functional teams across Platform, Services, SMB, and other domains.
• Support performance monitoring and contribute to reliability and scalability improvements.
• Participate in code reviews and maintain high code quality.
• Contribute to continual code quality and system architecture improvements.
• Troubleshoot and resolve technical issues.

Skills

Kotlin

Backend development

Microservices architecture

Cloud environments (AWS/Kubernetes)

PostgreSQL

Testing/Observability (JUnit, Grafana)

English proficiency

Tools

Kubernetes

AWS

PostgreSQL

JUnit

Grafana

Job description

Sii Poland is hiring a Kotlin backend developer to design, build, and maintain microservices for a modern fintech platform. The role involves collaborating with cross-functional teams across Platform, Services, SMB, and other domains to deliver robust solutions and improve system reliability.

The ideal candidate has at least 3 years of experience in software development, hands-on Kotlin in commercial projects, and familiarity with cloud environments and databases.