Senior Full Stack Engineer (Frontend-Oriented, AI-First Product Team)

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. Why is this role so important at Similarweb? We are looking for a Senior Full Stack Engineer with strong frontend and product orientation to build modern, scalable, AI-powered product experiences. This role combines deep expertise in client-side architecture and user experience with the ability to contribute across backend services, APIs, and platform infrastructure. You will work closely with product, design, backend, and data/AI teams to deliver end-to-end features while driving engineering excellence and leveraging AI throughout the development lifecycle. We are looking for engineers who are passionate about building great products, care deeply about user experience, and enjoy owning solutions from concept to production. So, what will you be doing all day? Full Stack Engineering Build end-to-end product experiences across frontend and backend systems Develop modern web applications using React, TypeScript, Vite, and NestJS Design scalable frontend architectures, reusable UI components, and shared platform capabilities Own complex features from concept to production across client and server layers Design and implement APIs, business logic, and integrations with internal and external services Optimize application performance, reliability, accessibility, and developer experience Collaborate closely with product, design, data, and infrastructure teams Contribute to testing strategies, observability, deployment pipelines, and platform improvements Lead technical decisions spanning frontend and backend domains Drive engineering best practices, maintainability, and scalability across the codebase Backend & Platform Development Design, build, and maintain backend services using NestJS Define API contracts and integration patterns across systems Participate in architectural decisions across frontend and backend systems Build scalable and reliable services supporting AI-powered product experiences Contribute to authentication, authorization, and platform capabilities Understand and optimize system performance across the full stack Support production operations, monitoring, troubleshooting, and incident resolution when needed Product & UX Translate product requirements into polished and intuitive user experiences Work closely with product designers to improve usability and interaction quality Balance speed, quality, technical excellence, and business impact Advocate for accessible, user-centric, and data-informed interfaces Contribute product ideas and technical insights throughout the product lifecycle Technical Leadership Provide technical leadership across frontend and backend domains Mentor engineers and conduct high-quality code reviews Drive architectural discussions and engineering best practices Improve testing, observability, CI/CD, and application reliability Promote ownership and accountability from design through production Help establish scalable engineering processes and standards AI-Augmented Engineering Use AI coding tools effectively (Cursor, Copilot, Claude, ChatGPT, etc.) Critically evaluate, validate, and improve AI-generated code Design efficient workflows for AI-assisted development Integrate AI capabilities into product experiences where relevant Understand the limitations, risks, and tradeoffs of LLM-based systems Contribute to engineering productivity through AI tooling and automation Collaborate with AI and data teams to build AI-native product experiences This is the perfect job for someone who: 5+ years of software engineering experience Strong experience building production-grade web applications across frontend and backend layers Expert-level proficiency in React, TypeScript, HTML, and CSS Experience developing backend services using Node.js, NestJS, or similar frameworks Strong understanding of API design, authentication, and integration patterns Experience designing scalable frontend architectures and reusable component systems Deep understanding of state management, rendering, caching, and performance optimization Experience working with REST APIs and modern frontend data-fetching patterns Strong understanding of web application performance, accessibility, and responsive design Experience with testing methodologies, monitoring, and observability practices Strong product mindset and user experience intuition Excellent communication, collaboration, and problem-solving skills AI & Modern Engineering Hands-on experience using AI development tools in daily workflows Ability to validate, debug, and improve AI-generated code Understanding of prompt engineering for software development workflows Familiarity with AI-powered product patterns and user experiences Ability to work effectively in fast-paced, iterative environments Nice to Have Experience building AI-native or AI-assisted product experiences Experience integrating LLMs, agents, RAG systems, or AI platforms into products Experience working in high-growth SaaS or product-driven companies Familiarity with cloud infrastructure and modern DevOps practices Experience with analytics, experimentation, and product measurement frameworks What We’re Looking For A product-minded engineer who enjoys building exceptional user experiences while owning technical solutions end-to-end. Someone who can comfortably move between frontend, backend, architecture, and product discussions, leverage AI effectively in their workflow, and help shape the next generation of AI-powered products **At Similarweb, collaborating with our colleagues in-office creates a more connected, unified culture. Our best work is a product of our face-to-face collaboration, with the ability to work partially from home.** Why you’ll love being a Similarwebber: You’ll actually love the product you work with: Our customers aren’t our only raving fans. When we asked our employees why they chose to come work at Similarweb, 99% of them said “the product.” Imagine how exciting your job is when you get to work with the most powerful digital intelligence platform in the world. You’ll find a home for your big ideas: We encourage an open dialogue and empower employees to bring their ideas to the table. You’ll find the resources you need to take initiative and create meaningful change within the organization. We offer competitive perks & benefits: We take your well-being seriously, and offer competitive compensation packages to all employees. We also put a strong emphasis on community, with regular team outings and happy hours. You can grow your career in any direction you choose: Interested in becoming a VP or want to transition into a different department? Whether it’s Career Week, personalized coaching, or our ongoing learning solutions, you’ll find all the tools and opportunities you need to develop your career right here. Diversity isn’t just a buzzword: People want to work in a place where they can be themselves. We strive to create a workplace that is reflective of the communities we serve, where everyone is empowered to bring their full, authentic selves to work. We are committed to inclusivity across race, gender, ethnicity, culture, sexual orientation, age, religion, spirituality, identity and experience. Our culture of equality and mutual respect also helps us better understand and serve our customers in a world that is becoming more global, more diverse, and more digital every day. We will handle your application and information related to your application in accordance with the Applicant Privacy Policy available here.