The Senior Software Engineer will collaborate with Product Managers and cross-functional engineering teams to elicit, analyze, and document comprehensive software requirements, translating them into detailed architectural and design specifications for the development of new software applications and product functionalities. This role involves leading the full software development lifecycle, encompassing project planning, execution, and deployment, for complex software engineering projects in programmatic advertising and Unified ID 2.0 open-source identity solution with a focus on the implementation and delivery of enhancements and features. The engineer will conduct comprehensive debugging, troubleshooting, and code remediation for production-level Unified ID 2.0 software services across a diverse technology stack, including Java, C#, Python, C++, and JavaScript, ensuring optimal system stability and performance. Additionally, the role includes driving the design, development, and end-to-end ownership of scalable, high-performance systems across the core components of a large-scale Demand Side Platform (DSP), including real-time bidding infrastructure, campaign APIs, reporting systems, audience targeting, and data pipelines. The engineer will also provide technical mentorship and guidance to junior software engineers, fostering their professional development through code reviews, architectural consultations, and constructive feedback on their technical contributions. Critical production support for deployed software applications is also a key responsibility, participating in on-call rotation to diagnose, resolve, and mitigate high-priority technical incidents and ensuring minimal system downtime. The role requires authoring public-facing documentation to help external clients effectively understand, integrate with, and utilize the Unified ID 2.0 APIs and SDKs, as well as engaging with industry partners and key customers at a technical level to provide deep insights and advice into the Unified ID 2.0 integration best practices and speed up adoption.