Senior Kotlin Microservices Engineer - Fintech Platform

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

Benefits offered by this job

Great Place to Work

Centre of internal trainings

Profit sharing

Regular integration events and trips

Medical care

Job summary

Sii Poland is looking for an experienced software engineer to join a fintech platform that integrates expense management, payments, and accounting tools for partner systems. You will design and build scalable Kotlin-based microservices and collaborate with cross-functional teams to deliver robust finansial solutions.

You will mentor teammates, participate in architecture decisions, and drive migrations while optimizing performance and reliability in cloud-native environments such as AWS and

Qualifications

• Minimum 5 years of professional experience in software development.
• Expertise in Kotlin, microservices, and distributed systems.
• Experience with cloud environments (AWS, Kubernetes).
• Proficiency with PostgreSQL, testing frameworks (JUnit, Testcontainers), and Grafana.
• Strong problem-solving and collaborative mindset to mentor teammates.
• Very good knowledge of English (min. B2).
• Residing in Poland required.

Responsibilities

• Lead design, build, and maintenance of scalable microservices primarily using Kotlin.
• Collaborate with cross-functional teams to develop solutions across Platform, Services, SMB, and more.
• Analyze system performance and implement optimizations for reliability and scalability.
• Participate in code reviews, post-mortems, and mentor other engineers.
• Improve architecture and quality, guiding the team through migrations and technical challenges.

Skills

Kotlin

Distributed systems

Microservices

AWS

Kubernetes

PostgreSQL

Testcontainers

JUnit

Grafana

English (B2)

Tools

PostgreSQL

JUnit

Testcontainers

Grafana

AWS

Kubernetes

React

TypeScript

Job description

Sii Poland is looking for an experienced software engineer to join a fintech platform that integrates expense management, payments, and accounting tools for partner systems. You will design and build scalable Kotlin-based microservices and collaborate with cross-functional teams to deliver robust finansial solutions.

You will mentor teammates, participate in architecture decisions, and drive migrations while optimizing performance and reliability in cloud-native environments such as AWS and