Senior Software Engineer I, Machine Learning, Search Systems

• Owning and operating next-gen retrieval infra and other search backends that power Etsy's core retrieval layer.
• Unify our retrieval infrastructure (lexical and ANN infra) across Etsy products, simplify system architecture, and enable ML-based rankers in retrieval.
• Building and maintaining scalable, low-latency systems that meet strict SLAs and power live A/B experiments.
• Collaborating closely with applied scientists, Data Platform, ML Enablement teams, and product engineers to integrate new retrieval models and unlock advanced ranking capabilities.
• Utilizing numerous AI tools to unlock both individual and team velocity, developing agentic workflows while improving developer experience.

• Design, build, and maintain search backend systems and infrastructure.
• Partner with ML modeling teams to productionalize new retrieval and ranking models efficiently at scale.
• Ensure reliable data pipelines, index health, and performance.
• Develop features around indexing, query execution, and ranking infrastructure to improve latency, throughput, and system resilience.
• Collaborate with cross-functional partners across other Search ML and Enablement Teams.
• Contribute to a culture of technical excellence, mentorship, and continuous learning through regular code reviews, design discussions, and performance feedback.
• Of course, this is just a sample of the kinds of work this role will require! You should assume that your role will encompass other tasks, too, and that your job duties and responsibilities may change from time to time at Etsy's discretion, or otherwise applicable with local law.

• You build and ship production ML systems, ideally in real-time search, recommendation, or ads systems.
• You have strong engineering and coding skills, with the ability to write high quality production code. Proficiency in Python, Scala, Java and/or other equivalent languages.
• You have experience with system performance optimization, caching strategies, and scaling high-throughput, low-latency services.
• You turn ideas into deeply reliable and well tested code that other people - or you, six months into the future - will find easy to comprehend and modify.
• You are a mindful, empathetic, and communicative member of your team.
• Hands-on experience with AI and agentic frameworks, including designing and building agentic workflows.
• Familiarity with modern retrieval and ranking techniques, including neural retrieval, semantic search, and transformer-based models is a plus.

At Etsy, we believe that a diverse, equitable, and inclusive workplace furthers relevance, resilience, and longevity. We encourage people from all backgrounds, ages, abilities, and experiences to apply. Etsy is proud to be an equal opportunity workplace and is committed to equal employment opportunity regardless of race, color, ethnicity, ancestry, national origin, religion or creed, sex, pregnancy (including childbirth and related medical conditions), gender, gender identity or expression, sexual orientation, age, citizenship or immigration status, marital or familial status, physical or mental disability, medical condition, genetic information, military or veteran status, or any other characteristic protected by applicable federal, state, or local law. If, due to a disability, you need an accommodation during any part of the interview or hiring process, please let your recruiter know and we will work with you to meet your needs. While Etsy supports visa sponsorship, sponsorship opportunities may be limited to certain roles and skills.