Senior Software Engineer I, Decision Systems

Etsy•New York, NY

14d•$164,000 - $193,000•Hybrid

About The Position

Decision Systems turns decisions and confidence signals into adaptive production systems that safely control exposure, payouts, and friction at scale. As a Senior Software Engineer on this team, you will lead projects aligned to your squad’s objectives in the Trust & Safety space. You will design and build decisioning services and pipelines that combine rules, model outputs, and human feedback into high throughput, low-latency systems. You will turn risk and enforcement strategies into concrete, observable controls that protect Etsy’s buyers, sellers, and business. You will collaborate across Risk, Operations, and other engineering teams to build for the external users who experience the outcomes of these decisions. This is a full-time position reporting to the Engineering Manager, Decision Systems. In addition to salary, you will also be eligible for an equity package, an annual performance bonus, and our competitive benefits that support you and your family as part of your total rewards package at Etsy. For this role, we are considering candidates based in the United States. Candidates living within commutable distance of Etsy’s Brooklyn Office Hub may be the first to be considered. For candidates within commutable distance, Etsy requires in-office attendance once or twice per week depending on your proximity to the office. Etsy offers different work modes to meet the variety of needs and preferences of our team. Decision Systems sits within Etsy’s Detection & Enforcement vertical, partnering closely with ML Engineering and Operations teams to build and evolve the systems that enact decisions at scale. The team is purposeful, focused on protecting the marketplace while minimizing unnecessary friction for trustworthy buyers and sellers. It is highly collaborative and cross-functional, building strong relationships with PMs, data scientists, analysts, and operations partners to align on risk strategies and enforcement behavior. The team is data-informed, using logs, metrics, and feedback from Ops to iterate on controls and improve decision quality over time. As a Senior Engineer, your day-to-day involves a mix of technical leadership, hands-on implementation, and cross-functional collaboration focused on building robust and secure enforcement systems. You will design and build decision systems, implement and evolve services that evaluate signals, scores, and rules to produce consistent enforcement outcomes (e.g., holds, reviews, limitations). You will collaborate across teams, partnering with Ops, Analytics, ML and Product to clarify requirements, align on tradeoffs, and share impact. You will join partners in incident remediation as needed to identify patterns of abuse and shut them down. You will mentor and elevate others via pairing, code reviews, and sharing context. You will help others break down problems and reason about risk tradeoffs. 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.

Requirements

Experience crafting and operating backend services that make or orchestrate automated decisions (for example, risk controls, rules engines, or workflow/decision systems), ideally in a large-scale, distributed environment.
Familiarity with the world of cybersecurity, particularly financial fraud.
Proficiency in at least one backend language such as PHP, a frontend language like Typescript, and a query language like SQL- and you’re comfortable learning the rest of our stack as needed.
Use data, experimentation, and engineering principles to shape solutions, and you incorporate what you learn back into the system.
Enjoy collaborating with a diverse set of partners, and you build trust through empathy and follow-through.
Take ownership in ambiguous spaces, while bringing in the right collaborators and asking for guidance when it unblocks the work.
Invest in tests, monitoring, and documentation.
Use incidents and surprises as input to harden systems and improve craft.

Responsibilities

Lead projects aligned to your squad’s objectives in the Trust & Safety space.
Design and build decisioning services and pipelines that combine rules, model outputs, and human feedback into high throughput, low-latency systems.
Turn risk and enforcement strategies into concrete, observable controls that protect Etsy’s buyers, sellers, and business.
Collaborate across Risk, Operations, and other engineering teams to build for the external users who experience the outcomes of these decisions.
Design and build decision systems
Implement and evolve services that evaluate signals, scores, and rules to produce consistent enforcement outcomes (e.g., holds, reviews, limitations).
Collaborate across teams
Partner with Ops, Analytics, ML and Product to clarify requirements, align on tradeoffs, and share impact.
Join partners in incident remediation as needed to identify patterns of abuse and shut them down.
Mentor and elevate others
Mentor other engineers via pairing, code reviews, and sharing context.
Help others break down problems and reason about risk tradeoffs.