Commerce Media Tech, part of Team Internet Group, is a dynamic ad-tech company based in Kraków. We’re passionate about building cutting-edge software that powers smarter, more effective online advertising. Our diverse team of software engineers, UX designers, product managers, marketers, and other talented professionals work together to deliver innovative advertising solutions for brands, agencies, and digital marketers worldwide.We're the team behind Zeropark, a trusted performance marketing platform. Now, we're building something new from the ground up — a next-generation Commerce and Retail Media platform.

What you'll be working on:

A greenfield project with the chance to shape its technical direction
Scalable, lightweight architecture for publishers, advertisers, and retailers
AI-driven real-time shopping intent matching based on page context
Cleanroom data integrations for precise attribution and targeting
Natural language campaign management via our MCP (Model Context Protocol) and AI agents
Innovative ad formats tailored for commerce and retail media

Key outcomes of the role

Our Team Culture:We're a tight-knit, motivated group that works end-to-end — from planning and building to deploying and maintaining. We collaborate closely with the business team and have full access to production environments, with no external ops or support layers.Our stack

Kotlin, Java 24/25
Frameworks: Spring, Spring Boot, Spring Data, Spring Cloud
Communication: Kafka (MSK), REST
AWS: ECS, Fargate, Lambda, ECR, CodeDeploy, Cognito, Route53 and more
Storage: ClickHouse, Aurora, DynamoDB, Elasticache, MemoryDB, Redshift, S3
Frontend: Typescript, Angular, Vue, Nx
Tools: Terraform, Gradle, Docker, GitHub Actions
Monitoring: DataDog, PagerDuty

Key responsibilities

Build new features using AWS services at scale
Design architecture with focus on scalability and maintainability
Work closely with Product and Business teams
On-call rotation(paid, once per 8 weeks after onboarding)

About you

5+ years of backend engineering experience (JVM ecosystem)
Bring demonstrable experience in building distributed systems
Know your way around testing (unit, integration)
Comfortable diving into frontend work when necessary
Own your work end-to-end from design decisions to production
AWS or other major cloud provider experience
Daily use of AI coding tools (eg Claude Code, Copilot, Cursor) with critical thinking
Be able to communicate clearly and work independently
Fluent in Polish and English

Experience and skills that will help you succeed

Kotlin experience (or willingness to learn - it's our primary language)
Kafka or similar event streaming platforms
Big Data processing using Apache Spark

Senior Software Engineer

Commerce Media Tech