Software Development Engineer, Seller Economics & Fees
Core
Design, build, ship, and operate fee calculation systems and AI-driven tools for 2+ million sellers across 23 countries, processing ~68.5B transactions.
Role type
Senior IC Software Development Engineer (Seller Economics)
Builds
Fee Calculation Engine, ML-based item classification, seller-facing AI surfaces, and agentic infrastructure
Domain
E-commerce / Seller Economics / Distributed Systems
Deliverable
production ML models
Required skills
C#, C++, Java, or Perl; Distributed systems design; Large-scale multi-tiered application development; AI-native engineering practices; Multi-agent workflows; Formal verification (SMT); Self-improving RL loops
Preferred skills
Machine Learning fundamentals; Large Language Model (LLM) architecture and optimization; Full SDLC experience including testing and operations
Technologies
SMT, RL, LLMs, C#, C++, Java, Perl
Responsibilities
Design and implement software solutions for major features; Identify root causes of operational issues and implement permanent fixes; Mentor and coach fellow engineers through code reviews; Evaluate new technologies and approaches to solve problems; Operate AI-native engineering practices using AI-assisted coding and agentic tools
Seniority
Senior, hands-on IC