Senior Software Engineer - Personalization

As a Senior Software Engineer on the Contentful Personalization Team, you will solve complex customer problems and deliver value through end-to-end personalization solutions. You will work across high-performance backend services, developer-facing frontend tools and SDKs, infrastructure, and observability to help customers deliver personalized content experiences in a performant, reliable, and developer-friendly way.

What you'll do

• Design, develop, and maintain high-performance backend services and APIs with a focus on reliability, scalability, and low latency.
• Deliver end-to-end solutions across backend services, React-based frontend experiences, and developer-facing SDKs, libraries, and tools.
• Implement complex CDN and edge-based caching solutions that allow users to retrieve personalized content in the most performant way.
• Solve technical challenges in creative ways, balancing the trade-off between performance and elegant software architecture.
• Continuously monitor and optimize system performance through benchmarking, while making sure systems are well instrumented for observability.
• Implement defensive coding practices and guarantee correctness and maintainable code through automated testing.
• Use AI-assisted and agentic coding tools responsibly to improve engineering workflows, while maintaining high standards for code quality, security, testing, and review.
• Participate actively in Agile ceremonies, including planning, refinement, reviews, and retrospectives, to help the team deliver customer value and continuously improve.

What you'll need

• Proven experience building APIs and services that efficiently handle large volumes of traffic.
• Strong proficiency with server-side TypeScript and API protocol design.
• Experience delivering full-stack solutions, including React-based frontend experiences and SDKs, libraries, or tools for developers.
• Experience with serverless architectures, ideally edge compute environments such as Cloudflare Workers.
• Experience with CDN operations and caching strategies to optimize system performance.
• Hands-on experience with benchmarking, instrumenting code for observability, and performance optimization for large-scale systems.
• Proficiency in using CI/CD pipelines and maintaining automated tests, including unit and end-to-end tests.
• A proactive approach with a strong sense of ownership and great communication skills in English.