Full Stack Developer

At Similarweb, we are revolutionizing the way businesses interact with the digital world by revealing to them everything that happens online.

Our unique data and solutions empower over 4,300 customers globally, including industry giants like Google, eBay, and Adidas, to make game-changing decisions that drive their digital strategies.

In 2021, we went public on the New York Stock Exchange, and we continue to reach new heights! Come work alongside Similarwebbers across the globe who are bright, curious, practical and good people.

We are looking for a Senior Fullstack Engineer with a strong backend orientation to join the development of our scalable, AI-powered product systems.

What You'll Do:

Join a role that combines deep backend expertise with solid frontend fluency and product thinking, along with the ability to leverage AI tools effectively across the development lifecycle. You will work closely with product, design, frontend, and data/AI teams to build reliable, performant systems and intuitive user experiences, while driving engineering excellence and modern development practices. Your contributions will shape the technical foundation of an AI-first product and directly influence the experience of end users.

What does the day to day of a Senior Fullstack Engineer at Similarweb look like:

Your daily work will span backend architecture, frontend collaboration, and AI-augmented development, engaging directly with the systems that power our product.

Your role will include:

• Design and build scalable, maintainable backend services using NestJS (Node.js/TypeScript) and/or Python
• Own API design, contracts, and versioning across services
• Design and optimize data models, database schemas, and query performance
• Implement authentication, authorization, and secure API integration patterns
• Build reliable data-fetching layers, caching strategies, and async processing (queues, jobs, events)
• Lead backend technical decisions, code quality standards, and system architecture
• Ensure system scalability, fault tolerance, and observability (logging, monitoring, alerting)
• Contribute to CI/CD pipelines and deployment practices for backend services
• Collaborate on frontend applications built with React, TypeScript, and Vite, and contribute to API contracts from the consumer's perspective
• Partner with frontend engineers to align on data shapes, performance, and UX constraints
• Translate product requirements into robust, scalable technical solutions, working closely with product and design