Kotlin Backend Engineer – Fintech Microservices

Sii Poland; Katowice; On-site; PLN 180,000 - 240,000; Full time

Benefits offered by this job

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

Job summary

Sii Poland is hiring a backend developer with Kotlin to design, build, and maintain microservices powering a modern fintech platform in Katowice. You will work with cross-functional teams to deliver scalable solutions and ensure reliability and performance across the system.

Candidates should have 3+ years of experience in software development, hands‑on Kotlin experience, and strong English communication. Residency in Poland is required.

Qualifications

• Minimum 3 years of professional experience in software development.
• Hands‑on experience with Kotlin in commercial projects.
• Experience building backend systems and working with microservices architecture.
• Basic experience with cloud environments (e.g., AWS, Kubernetes).
• Experience with relational databases (e.g., PostgreSQL) as well as testing and observability tools (e.g., JUnit, Grafana).
• Good command of English and residency in Poland.

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 improvements in reliability and scalability.
• Participating in code reviews and maintaining high code quality standards.
• Contributing to the continuous improvement of code quality and system architecture.
• Troubleshooting and resolving technical issues.

Skills

Kotlin

Backend development

Microservices architecture

English communication

Tools

AWS

Kubernetes

PostgreSQL

JUnit

Grafana

Job description

Sii Poland is hiring a backend developer with Kotlin to design, build, and maintain microservices powering a modern fintech platform in Katowice. You will work with cross-functional teams to deliver scalable solutions and ensure reliability and performance across the system.

Candidates should have 3+ years of experience in software development, hands‑on Kotlin experience, and strong English communication. Residency in Poland is required.