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Drive product and business impact through statistical modeling, experiment design, Bayesian marketing analysis, machine learning, NLP, LLM applications, and classifier implementation. Build growth metrics, monitoring pipelines, evaluation datasets, and AI trigger systems across search and Duck.ai. Analyze privacy-constrained data, deploy production-grade models, optimize SQL queries, and lead complex projects from scoping through production with minimal direction.

As a Senior Backend Engineer at DuckDuckGo, you'll lead backend projects, mentor engineers, and develop AI-enhanced features for the company's privacy-centric product line.

Manage paid media and app acquisition campaigns across Google, Microsoft, Apple, and other channels. Plan, execute, test, optimize, and analyze campaigns to drive profitable user and subscriber growth. Lead incrementality testing, creative experimentation, channel expansion, app economics modeling, and spend optimization. Own high-priority marketing projects and communicate recommendations using data, experimentation, and strategic judgment.

Build and lead high-performance browser features in modern C++ and Chromium, including tracker blocking, subscription integrations, and responsiveness monitoring. Own complex projects from proposal through post-mortem, solve ambiguous technical problems, make architecture decisions, collaborate asynchronously with product and design, and use metrics to evaluate outcomes in a large-scale consumer codebase.

Own web compatibility triage and incident response across DuckDuckGo browsers on Mac, Windows, iOS, and Android. Debug complex web applications and third-party code, distinguish site, browser, and privacy-related issues, reverse-engineer obfuscated code, build durable cross-platform fixes, and develop automation and LLM agent tooling to reproduce and triage breakage. Lead ambiguous projects independently and communicate with technical and non-technical stakeholders.

Lead and own major components of DuckDuckGo's privacy technology using Go, Node.js, Python, and Perl. Design and implement privacy features, improve search and AI features without compromising privacy, build tracker-detection features, participate in privacy reviews and audits, and mentor engineers over time.