Staff Engineer @ Adevinta | Open Source Advocate | AI Pioneer | Tech Writer & Speaker
Building scalable systems, mentoring engineers, and pushing the boundaries of AI-assisted development.
I'm a seasoned software engineer with 15+ years of experience building and scaling production systems. Currently at Adevinta (Kleinanzeigen), I design and maintain high-throughput backend systems serving 10,000+ requests per second while championing modern engineering practices across the organization.
As a Staff Engineer, I bridge the gap between deep technical execution and strategic product leadership, working alongside product, UX, business, and engineering teams to deliver robust, scalable solutions.
- 5+ years designing, building, and maintaining production systems at Kleinanzeigen
- Architecting services handling 10,000+ requests/second at scale
- Expert in greenfield development and brownfield system evolution
- Deep experience with microservices, event-driven architectures, and domain-driven design
- Several years of hands-on React, Next.js, and Astro development
- End-to-end system design spanning frontend, backend, data, and ML components
- Ensuring architectural coherence across the entire product stack
- Keeping pace with modern frontend ecosystems (TanStack, etc.)
- Daily work with dbt, Databricks, Airflow, and Python
- Building retail media systems with advanced search capabilities
- Data-native approach to system design and product development
- Bridging the gap between software engineering and data science
- Mentoring engineers from junior to senior, tech leads to heads-of-engineering
- Driving team success as a Staff Engineer through technical guidance and collaboration
- Fostering engineering excellence and best practices across the organization
- Building high-performing teams through systems thinking and continuous improvement
- AI Pioneer using AI to accelerate learning depth and breadth while maintaining quality
- Initiator of n8n adoption groups within the organization
- Host of Claude Coding Days to democratize AI-assisted development
- Championing the paradigm shift from AI-assisted to agentic coding
I regularly write about software engineering, architecture, and AI on sebastiansigl.com:
- System Architecture: Modular monoliths, microservices, and scaling strategies
- Event Sourcing: Practical patterns for event-driven systems
- Cloud Infrastructure: Docker, Kubernetes, AWS, and modern DevOps practices
- AI & Productivity: Leveraging AI for faster, deeper learning and development
- Data Engineering: Becoming a data engineer, working with modern data stacks
Languages: Python, Java, JavaScript/TypeScript, Go, SQL
Backend: Spring Boot, Domain-Driven Design, Event Sourcing, Microservices
Frontend: React, Next.js, Astro, Modern JavaScript Ecosystem
Data & ML: dbt, Databricks, Airflow, Apache Spark, Hadoop
Cloud & Infrastructure: AWS, Docker, Kubernetes, Terraform
Tools & Automation: n8n, Claude, GitHub Actions, GitLab CI/CD
I'm passionate about open source and believe in building technology that empowers others. I'm particularly interested in:
- Developer Tools & AI Integration: Making AI-assisted development accessible
- Data Infrastructure: Building robust, scalable data pipelines
- Engineering Excellence: Patterns, practices, and tools that improve software quality
- Knowledge Sharing: Documentation, guides, and educational content
- Projects that push the boundaries of AI-assisted development
- Open source tools for data engineering and ML operations
- Developer productivity and engineering effectiveness tools
- Systems that require end-to-end architectural thinking
- Website: sebastiansigl.com
- LinkedIn: linkedin.com/in/sesigl
- Bluesky: @sesigl
- X/Twitter: @sesigl
- Advanced agentic coding patterns and their implications for software development
- Modern frontend architecture patterns (TanStack, Server Components, etc.)
- Retail media systems and advanced search technologies
- Scaling AI adoption in engineering organizations
Open to interesting collaborations and conversations about software engineering, architecture, AI, and building great products.