Kotlin Backend Engineer – Fintech Microservices

Sii Poland; Województwo pomorskie; On-site; PLN 120,000 - 190,000; Full time

Benefits offered by this job

Great Place to Work

Centre of internal trainings

Profit sharing

Medical care

Job summary

Sii Poland is seeking a backend developer to join a fintech project focused on expense management and seamless integration with banks, accounting platforms, and HR tools. You will design, build and maintain Kotlin-based microservices for a fintech platform.

Collaborate with cross-functional teams to deliver scalable solutions, ensure performance and reliability, and participate in code reviews. English proficiency and Poland residency are required.

Qualifications

• 3+ years of professional software development experience.
• Hands-on Kotlin experience in commercial projects.
• Experience building backend systems and microservices.
• Basic exposure to cloud environments (AWS, Kubernetes).
• Experience with PostgreSQL and testing/observability tools (JUnit, Grafana).
• Good command of English.
• Residence in Poland.

Responsibilities

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

Skills

Kotlin

Backend development

Microservices

Cloud basics

Tools

AWS

Kubernetes

PostgreSQL

JUnit

Grafana

Job description

Sii Poland is seeking a backend developer to join a fintech project focused on expense management and seamless integration with banks, accounting platforms, and HR tools. You will design, build and maintain Kotlin-based microservices for a fintech platform.

Collaborate with cross-functional teams to deliver scalable solutions, ensure performance and reliability, and participate in code reviews. English proficiency and Poland residency are required.