About the team and the role:WHI Solutions, Inc., an eBay company, operates Nexpart, a B2B marketplace built for professional automotive and truck parts businesses. Nexpart plays a critical role in helping customers efficiently source and purchase the parts they need to keep their operations running smoothly and serve their own customers with speed and confidence.
The Nexpart engineering team builds and evolves the technology behind this marketplace. We are seeking a Senior Python Engineer, AI to help design, develop, and maintain scalable backend services, integrations, and platform capabilities that support critical business workflows and ongoing product innovation.
We are seeking an engineer with strong Python backend experience and a track record of building reliable, scalable services. In this role, you will work with cross-functional partners to develop practical solutions that support critical workflows and improve the performance and resilience of the platform.
What you will accomplish: - Define technical requirements in partnership with product, business, and engineering stakeholders
- Design, develop, and maintain Python-based applications & services that power core platform workflows
- Build and integrate scalable APIs and microservices for internal and external consumers
- Own backend system design for service reliability, scalability, maintainability, and operational excellence
- Optimize performance using distributed technologies (e.g., caching, message queues, event-driven architectures)
- Implement robust observability (logging, tracing, metrics), troubleshoot production issues, and improve system resiliency
- Participate in code reviews as both a contributor and reviewer; contribute to engineering standards and best practices
- Collaborate closely with development, QA, and business teams to deliver high-quality releases
- Create and maintain system and technical documentation as needed
- Leverage AI-powered development tools to improve productivity, code quality, and delivery speed
Applied AI/LLM Focus - Build and productionalize LLM-enabled features (e.g., workflow automation, intelligent routing, summarization, extraction)
- Design tool/function-calling services and orchestration layers for multi-step tasks
- Implement RAG-style retrieval patterns (embeddings, vector search, ranking) where it improves reliability and accuracy
- Develop evaluation and quality frameworks for AI outputs (offline evals, regression tests, safety/reliability checks)
- Collaborate on responsible AI practices: guardrails, data handling, deterministic behaviors, and auditability
What you will bring:- BA/BS in Computer Science or a related field, or equivalent practical experience
- 5+ years of professional Python development experience in production environments
- Strong experience building asynchronous, API-driven microservices (e.g., FastAPI, asyncio)
- Solid understanding of scalable backend architectures and service-to-service integrations
- Experience with distributed systems patterns (queues, caching, pub/sub, background processing)
- Strong understanding of REST APIs, authentication/authorization, and secure system design
- Experience with CI/CD pipelines and containerized deployment workflows
- Strong familiarity with Git and modern version control workflows
- Excellent English communication skills, both written and verbal
- Ability to work effectively in cross-functional, fast-paced environments
Preferred Qualifications:- Experience integrating LLM APIs in production and building robust, testable AI-enabled services
- Familiarity with prompt design, structured outputs, tool/function calling, and conversation/workflow state management
- Experience with embeddings, vector databases, retrieval pipelines, and/or ranking approaches
- Experience building AI evaluation harnesses (golden datasets, regression testing, quality metrics)
- Exposure to ML concepts relevant to applied product systems (classification, extraction, ranking, personalization)
- Experience with real-time or conversational interfaces (chat and/or voice) and streaming systems
- Proficiency in Spanish (or other major marketplace languages) to help evaluate and validate multilingual AI outputs
- Experience supporting high-traffic, consumer-facing applications
Why You'll Love Working Here- Build backend systems that support a global marketplace at scale
- Work on high-impact platform capabilities that increasingly leverage LLM/AI/ML
- Opportunity to influence technical direction and architecture
- A culture that values innovation, ownership, and continuous learning
- Competitive compensation and comprehensive benefits
Additional DetailsThe base pay range for this position is expected in the range below:
$118,800 - $205,600
Base pay offered may vary depending on multiple individualized factors, including location, skills, and experience. The total compensation package for this position may also include other elements, including a target bonus and restricted stock units (as applicable) in addition to a full range of medical, financial, and/or other benefits (including 401(k) eligibility and various paid time off benefits, such as PTO and parental leave). Details of participation in these benefit plans will be provided if an employee receives an offer of employment.
If hired, employees will be in an "at-will position" and the Company reserves the right to modify base salary (as well as any other discretionary payment or compensation program) at any time, including for reasons related to individual performance, Company or individual department/team performance, and market factors.
Remote roles are not eligible for U.S. visa sponsorship.
