Senior Software Engineer I, Machine Learning, Search Systems

About Etsy

Etsy operates as a global marketplace specializing in distinctive and creative products. We design, develop, and continuously improve technologies that link millions of sellers with buyers worldwide. Joining Etsy means working on meaningful challenges alongside passionate colleagues, creating impactful solutions while maintaining our human-centered commerce philosophy.

Our commitment is to build exceptional teams by hiring talented individuals, supporting their success from the outset, and encouraging career growth through meaningful development beyond promotions. We nurture trust and collaboration to facilitate exceptional performance.

Role Overview

We seek a Senior Software Engineer I specializing in Machine Learning to join our Search Systems team based in Dublin. This team manages the core retrieval and indexing platforms that enable rapid, dependable, and seamless search for millions of Etsy users. As part of a major infrastructure upgrade, the team is focused on unifying retrieval systems, simplifying architecture, and enhancing machine learning capabilities to boost relevance, system performance, and developer productivity.

This is a full-time position reporting directly to the Engineering Manager.

Team Overview

The Search Systems team falls under Search and provides foundational technology that supports scalable, high-quality search experiences. The team's mission involves ensuring Etsy's search stack functions with speed, reliability, and extensibility—handling hundreds of millions of listings while facilitating swift machine learning experimentation and innovation.

Key Responsibilities

• Manage and operate next-generation retrieval infrastructure and other backend systems powering Etsy's core search retrieval layer.
• Consolidate lexical and approximate nearest neighbor (ANN) retrieval infrastructure to streamline architecture and enable machine learning-based ranking in retrieval.
• Develop and maintain scalable, low-latency systems that comply with strict service level agreements and support live A/B testing.
• Collaborate closely with applied scientists, data platform teams, ML enablement groups, and product engineering to integrate new retrieval models and enhance ranking capabilities.
• Leverage a variety of AI tools to increase both individual and team productivity, crafting agentic workflows and elevating developer experience.
• Design, build, and sustain backend search systems and infrastructure.
• Work alongside machine learning model teams to efficiently scale and deploy new retrieval and ranking models in production.
• Ensure integrity of data pipelines, index health, and system performance.
• Create and improve features related to indexing, query execution, and ranking infrastructure aimed at enhancing latency, throughput, and resilience.
• Engage with cross-functional partners from other Search ML and Enablement teams.
• Promote a culture emphasizing technical excellence, mentorship, continuous learning through code reviews, design discussions, and proactive feedback.
• Perform additional duties as required, understanding that tasks and responsibilities may evolve over time in accordance with company policies and local laws.

Candidate Profile

• Experience building and deploying production machine learning systems, preferably within real-time search, recommendation, or advertising domains.
• Strong coding skills with the capacity to write clean, maintainable, and high-quality production software. Proficient in Python, Scala, Java, or comparable programming languages.
• Familiarity with system optimization techniques including caching, performance tuning, and managing scalable, high-throughput, low-latency services.
• Ability to produce reliable, well-tested code that is easily understandable and modifiable by team members over time.
• Demonstrated empathy, mindfulness, and effective communication within a team environment.
• Hands-on experience with AI frameworks enabling agentic workflows and associated design and development.
• Knowledge of contemporary retrieval and ranking methodologies such as neural retrieval, semantic search, and transformer-based models is advantageous.

Compensation and Benefits

The total compensation package includes base salary, annual bonuses, equity options, and comprehensive benefits accommodating employee and family wellbeing. Base salary is contingent on candidate location, skill set, and experience.

Work Location and Attendance

Priority is given to applicants within commuting distance of Etsy's Dublin office, with an expectation of attending onsite one to two days weekly depending on proximity. Remote candidates located beyond commuting range will be considered individually, requiring occasional office visits.

Equal Opportunity Statement

Etsy is strongly committed to fostering a diverse and inclusive workplace that promotes equity and relevance. We welcome applicants from all backgrounds, identities, and experiences. We provide accommodations for disabilities throughout the hiring process upon request. While Etsy supports visa sponsorship, availability may be limited depending on role and skills.