Senior Fullstack Engineer

Senior Engineer will be responsible for the development of the OnetAds platform (onetads.pl) and e-commerce services — Skapiec.pl and Lamoda.pl. The role involves active participation in building new functionalities, optimizing existing solutions, and supporting the Content Commerce area. The position requires solid fullstack experience with a focus on a modern stack based on React/Next.js and NestJS using Elasticsearch and PostgreSQL as main data layers.

• Minimum 4-5 years of experience in web software development
• Very good knowledge of React and Next.js
• Experience with NestJS
• Practical knowledge of Opensearch — indexing, searching, query optimization
• Experience with PostgreSQL — data modeling, query optimization, migrations
• Ability to design and implement API interfaces: GraphQL and REST
• Knowledge of Tailwind CSS
• Basic knowledge of AWS Cloud services (EC2, S3, RDS, CloudFront, etc.)
• Experience with Amazon EKS (Kubernetes on AWS)
• Experience working with AI agents / agentic coding tools: Claude Code, GitHub Copilot, Codex
• Ability to work independently and make technical decisions
• Knowledge of English

Nice to have:

• Knowledge of AWS SQS/SNS queues — messaging, event-driven architecture
• Experience in e-commerce, AdTech, or Content Commerce industry
• Experience with CI/CD (GitHub Actions)
• Knowledge of monitoring and observability tools (Grafana, CloudWatch, Prometheus)
• Experience with microservices and containerization

• Development and maintenance of the OnetAds platform and Skapiec.pl and Lamoda.pl services
• Designing and implementing new fullstack functionalities (frontend + backend)
• Building and developing API interfaces (GraphQL and REST)
• Optimizing search performance and indexing in Opensearch
• Collaborating with product and business teams in the Content Commerce area
• Participating in code reviews, architectural planning, and technical decisions
• Ensuring code quality, testing, and technical documentation