Senior Staff Software Engineer, Web Platform

Upwork is undergoing a platform transformation to meet the evolving demands of AI-native product experiences. As a Staff Software Engineer on the Web Platform team, you will lead the design and development of our next-generation web architecture, empowering teams across Upwork to build dynamic, agent-driven user interfaces with speed and confidence. You’ll play a pivotal role in defining how our platform supports modular, performant, and scalable frontend experiences. This includes driving the adoption of federated app shell architecture, pioneering horizontal micro apps, and optimizing developer workflows to support modern AI toolkits. Architect and build modular frontend infrastructure with hybrid rendering (SSR, edge functions, client hydration) to support dynamic AI-native UIs. Lead development of an app shell model to enable federated delivery of horizontal micro frontends across teams, with strong ownership boundaries and runtime flexibility. Develop and evangelize AI toolkit components , enabling common interaction patterns (clarify, retry, fallback, tone) to be reused across the platform. Mentor engineers and contribute to technical leadership across Product Engineering through architecture reviews, design discussions, and shared learning. Collaborate cross-functionally with Product, Design, and Infrastructure teams to align platform capabilities with user-facing needs.