Kotlin Backend Engineer for Fintech Microservices

Sii Poland; Warszawa; On-site; PLN 180,000 - 260,000; Full time

Benefits offered by this job

Profit sharing

Medical care

Open management

Centre of internal trainings

Team events

Job summary

Sii Poland is hiring a backend developer to design, build, and maintain microservices using Kotlin in a fintech-oriented platform. You will collaborate with cross-functional teams across multiple domains, support performance monitoring, and drive reliability and scalability improvements.

The role also emphasizes code reviews, architecture improvements, and ongoing learning within a dynamic, Polish-based team. English proficiency is required and relocation to Poland is expected.

Qualifications

• 3+ years of professional software development experience.
• Hands-on Kotlin in commercial projects.
• Experience building backend systems and microservices architecture.
• Basic experience with cloud environments (AWS, Kubernetes).
• Experience with relational databases (PostgreSQL).
• Good command of English.

Responsibilities

• Designing, building, and maintaining microservices using Kotlin.
• Collaborating with cross-functional teams to deliver solutions across Platform, Services, SMB, and other domains.
• Supporting system performance monitoring and contributing to reliability and scalability improvements.
• Participating in code reviews and maintaining high code quality standards.
• Contributing to continuous improvement of code quality and system architecture.
• Troubleshooting and resolving technical issues.

Skills

Kotlin

Backend development

Microservices

PostgreSQL

English

Tools

AWS

Kubernetes

JUnit

Grafana

Job description

Sii Poland is hiring a backend developer to design, build, and maintain microservices using Kotlin in a fintech-oriented platform. You will collaborate with cross-functional teams across multiple domains, support performance monitoring, and drive reliability and scalability improvements.

The role also emphasizes code reviews, architecture improvements, and ongoing learning within a dynamic, Polish-based team. English proficiency is required and relocation to Poland is expected.